There are urban colectivo's, but the city is small enough that it is best to walk. If you are coming from Comitan, you will get dropped off by the farmers market, which is also the point to catch a colectivo for the ruins. Ask directions for the central park to find most of the hotels, restaurants, atms etc. There is a different terminal for colectivo´s for Palenque and San Cristobal.
For most, Ocosingo is only a jumping off point for Laguna Miramar or Toniná. However, if you do decide to stay here, the town is friendly and0 not a bad place to stay a night. The centre has a leafy colonial style plaza, and near the colectivo terminal is the rowdy "peasents" market, where local farmers come to sell their produce.
The obvious attraction here are the ruins. There are also Automatic Teller Machines (ATM) in Ocosingo. Before heading into Laguna Miramar you should pull out any needed cash here. If you stay here a day, take a stroll around the central plaza in the evening or explore the farmers market in the morning.
Several restaurants around the plaza. If you can manage to find Hospedaje Esmeralda, head down that road and take the first left, along that street there are many super cheap and tasty comidors. Incidently, head up two or three blocks and then turn left for onward transport to Palenque.
There are a number of decent hotels off the main plaza that are priced between $15 and $30 USD. Budget travelers beware, at the time of writing, apparenlty there are no dormotories in town. For solo travelers, you might find it difficult to find anything cheaper than M$180. You could always arrive early, see the ruins, and then continue to San Cristobal or Palenque. Factor around 3 hours to see the ruins and the museum.
Hospedaje Esmeralda, Calle Central Nte 14 (Get to main plaza and ask for directions if you get lost.). Family owned and very helpful, it has a pleasant, leafy restaurant and rooms with shared bathroom starting at 180.00 Peso for one person. Clean and the water was hot. edit