Unfortunately there are no international connections, but Ilawa has good domestic connections with almost all major cities in Poland.
Schedules can be found on the PKP website 
There are two train stations - Ilawa Miasto (small) and Ilawa Glowna (big). Not all trains stop at Ilawa Miasto so try to get out at Ilawa Glowna.
Public transport is not well developed, but some does exist. A single ticket costs 1.9 PLN (0.5 EUR).
Taxis are available and tend to be cheap - around 3EUR within the city district. Tipping is not not obligatory. The cheapest Taxi corporations are Wodnik and Hallo Taxi. The most expensive taxis are in the train station.
Sadly, much of Ilawa was destroyed in World War II. However, some interesting attractions have survived.