Indianapolis International Airport  is the major airport in the state with flights to many cities around the country. Fort Wayne, Evansville and South Bend offer flights to nearby hub cities. Air service is also available from nearby airports in Chicago, Cincinnati and Louisville.
Numerous interstate highways enter and leave the state. Interstates 80 and 90 form the Indiana Toll Road in northern Indiana, linking Gary, South Bend and Ohio. Interstate 94 hugs most of Lake Michigan from Illinois to Michigan. Interstate 65 is the major north-south route from Gary south to Indianapolis then entering Kentucky at Louisville. Interstate 70 is the busiest east-west route linking Illinois (at Terre Haute) with Ohio (at Richmond), passing through Indianapolis midway. Interstate 74 does the same thing, except it enters near Danville, Illinois and leaves near Cincinnati. Interstate 64 crosses southern Indiana from Illinois (25 miles northwest of Evansville) to New Albany. Interstate 69 runs from northeast Indiana, out of Michigan, through Fort Wayne to Indianapolis, where it ends (there are plans to extend it to Evansville and eventually to Texas). Interstate 275 (the Cincinnati bypass) briefly enters Indiana for about five miles. US 41 extends from Gary to Evansville and is the major north-south route through western Indiana.
Indiana's motto is "The Crossroads of America" and it is deserving. Indiana has more Interstates (14) than any other state its size, although the original name comes from all the railroad tracks that went through the state.
Amtrak offers a daily train service from Indianapolis to Chicago and vice versa. The fare is reasonable (about 15-25 dollars each way). The train also passes through Lafayette as well as a few other towns along its way to Chicago. The time of travel is roughly about 4.5 hours as compared to about 3-3.5 hours by car.
South Shore Line links Northern Indiana to Chicago, stopping at Hammond, East Chicago, Gary, Ogden Dunes, Beverly Shore, Michigan City, Hudson Lake and South Bend. It terminates at Chicago's Millennium Station. The overall travel time from South Bend to Chicago (and vice versa) 2.5 hours. The line utilizes a zone-based fare system, with prices rising based on the distance, and the prices drop slightly on the weekends. The prices range from $3.80 - $10.75 on weekdays and $3.00-$9.00 on weekends.
Your traditional sightseeing in Indiana belongs in Indianapolis, which is flush with big museums, an inordinate quantity of giant monuments and memorials, and a very nice canal walk with paddleboats and public art.
Outside the cities, and outside of the seemingly endless farmland in the plains, are a host of parks and outdoor recreation areas worth visiting. Without a doubt, the one to see, if you must choose, is Indiana Dunes National Lakeshore (and Indiana Dunes State Park). The dunes are enormous, the water crystal clear, the swampy forests beautiful, and the far-off industrial views intriguing.
late AprilThunder Over LouisvilleClarksville and Jeffersonville.  The opening ceremonies to Louisville, Kentucky's Kentucky Derby Festival. Thunder Over Louisville is the largest annual fireworks show in the country, and the best viewing is along the Indiana shore of the Ohio River. If you plan to get a good seat, prepare to come the day before and camp. In the afternoon, private and military aircraft provide a magnificent airshow. After sunset, the fireworks begin and last nearly half an hour.
Early-Mid AugustIndiana State Fair State Fairgrounds, Indianapolis.  The biggest summer event in the state. A trip to Indiana isn't complete without a trip to the fair. Animals, crafts, art, rides, dancing, eduation, enviromentalism, Hoosier Pride and FOOD!! I go at least 2-3 times within the two week period. They also have live music and concerts. Prairie Home Companion comes every other year.
Mid-SeptemberLanesville Heritage WeekendLanesville.  A fall festival typical of many in southern Indiana. Is similar to a county fair, but later in the year. Local food and crafts are available, while rides and tractor and truck pulls provide entertainment.
Early OctoberWest Side Nut Club Fall FestivalEvansville. Called the second largest street festival in the United States after Mardi Gras. It takes place on several blocks of Franklin Street on the west side of the city during the first full week of October. The main attraction of the festival is its food booths which sell a large variety of foods including brain sandwiches and chocolate-covered grasshoppers. The festival draws over a hundred thousand visitors every fall.
Early-mid OctoberHarvest Homecoming FestivalNew Albany.  The largest festival in southern Indiana brings participants from miles around. The festivities begin with a Saturday morning parade through the streets of New Albany. THe festival lasts for several weeks, and includes vendor booths downtown and carnival rides.
Mid OctoberFeast of the Hunters' MoonLafayette,  The Feast re-creates early 18th century life near the site of Fort Ouiatenon, a French trading outpost.
College sports- Indiana is home to many Division I NCAA schools, including: Ball State University (Muncie) Butler University (Indianapolis), IUPUI (Indianapolis), Indiana State University (Terre Haute), Indiana University (Bloomington), Purdue University (West Lafayette), University of Evansville (Evansville) and University of Notre Dame (South Bend).
Racing- The Indianapolis 500 race is the most attended sporting event in the world. It's common to see many vendors and spectacular displays during the pre-race (most notably the singing of "Back Home Again In Indiana" by Jim Nabors and the overfly of the stealth bomber at the conclusion of the National Anthem). Also don't forget the Allstate 400 (formerly the Brickyard 400) NASCAR race held every summer in Indianapolis. IRP (Indianapolis Raceway Park) also holds the grand nationals of drag racing at it's facility. IRP is located about 10 miles west north-west of Indianapolis in Hendricks County
Racing- Salem Speedway.  Home to many small-circuit races throughout the year, Salem is often called the "fastest half mile in the world." With only a chain-link fence separating the pit lane from the infield, Salem offers a more interactive fan experience than many larger tracks.
Cuisine throughout much of the state is typical Mid-western, with the occasional odd dish like Corn Casserole. Outside of the main cities most of the restaurants are diners or family-style, while in the bigger cities you can find all sorts of varied cuisine. Indianapolis, in particular, has a very cosmopolitan selection of ethnic restaurants from around the world. Lake County, as in most everything, diverges from the norm in Indiana, and is a better place to find Chicago-style food like hot dogs and pizza.
Hoosiers know how to drink! Wherever you are, you would be hard pressed to not find a bar. The trendiest part of the state for a drink is probably Broad Ripple in Indianapolis, but you will find streets packed with bars and pubs throughout the cities of the state, especially near major universities in Bloomington, West Lafayette, and South Bend. Micro-breweries are present in all the major cities, Upland from Bloomington is especially popular and available throughout the state. Note too, that drink prices can be very low in Indiana—especially out of the Nine-County Region. It's not uncommon to find domestic bottled beer for $1 during the week, with other varying specials.
For dancing and nightlife, the main options are in and around Indianapolis and Fort Wayne, as well as by the major universities.
By law, liquor stores are closed on Sundays throughout the state. Depending on what part of the state you are in, a short jaunt across state lines can solve this problem. Along many major routes in and out of the state, one can often find "state line" liquor stores that cater to Sunday customers from Indiana.
Bars and restaurants are allowed to serve beer, wine, and liquor seven days a week, between the hours of 7:00 am and 3:00 am (the following morning), local time. Hours for bars can vary by population density and owner preference, but the vast majority of full-service "chain" restaurants with alcohol sales will not remain open beyond 11 pm or midnight. In most localities however, one can always find a neighborhood bar or nightclub that will serve drinks right up to 3:00. In all substantial cities, almost all bars will remain open until this time.
There have been many rumors about a liquor law in Indiana that prohibits the "take home" sale of cold beer. This is absolutely false. Throughout the state in any liquor store, Village Pantry service stations, and some grocery stores it can be purchased cold. Liquor stores that sell hard alcohol cannot sell pop or soda cold, rather it must be at room temperature.
Crime - Largely rural, Indiana has a fairly low crime rate per capita. In 2006 (the latest year for which data is available) it ranked 29th in crimes per 100,000 population. Large urban areas are exceptions like the former steel town Gary and the outlying Chicago area in the Northwest and certain segments of Indianapolis.
Weather - While outside of Tornado Alley, Indiana has a fairly high occurrence of tornados. You might want to check the Tornado safety page if you are visiting Indiana.
The vast majority of Indiana is on Eastern Time and -- as of 2006 -- does now observe Daylight Savings Time. The five counties of Northwestern Indiana (near Chicago) as well as several counties around Evansville are on Central Time
Illinois - Chicago, the largest city in the Midwest, is located just across Indiana's western border, making it an ideal day-trip destination.
Kentucky - Indiana's neighbor to the south is known for its rolling hills, horses, and rural inhabitants, offering travelers a less-visited but tremendously beautiful destination.
Ohio - Located to the east of Indiana, the city of Cincinnati is a short drive from southeastern Indiana.
Michigan - Indiana's northern neighbor borders four of the five Great Lakes and features stunning natural beauty.
This is a usable article. It gives a good overview of the region, its sights, and how to get in, as well as links to the main destinations, whose articles are similarly well developed. An adventurous person could use this article, but please plunge forward and help it grow!