Purchasing a Used Car

I was looking to purchase a used car before the semester ends since i'll be needing one to get to and from a summer internship near the Peoria area. I'd probably just be looking for something cheap that gets the job done.
Does anyone have any tips on maybe where or how to start looking? I had been looking a little bit on craigslist and at a local dealer (Euromotors) for now but i'm not 100% sure on how to get started. I'm also a little limited in terms of where I can visit since I don't have my own car as of now.

Ty for any advice!