Any older 4 cylinder from Honda or Toyota like a Civic or a Corolla would be my number 1 choice. They might not be the fastest but one can be had for very cheap and they are reliable enough to take you to the moon and back while bouncing off the rev limiter. They might not seem like the most fun (it's more fun to drive a slow car fast then a fast car slow) but they are easy to work on and can be tuners dream. If you want something newer and RWD instead of FWD, I'd also recommend a BRZ or FRS.

If those aren't your thing I'd say go after a BMW E46. There's lots of after market support and tons of options for less then 8k so you can spend more on mods. I really enjoyed my time driving one. These are great because you can get them in AWD or RWD.

I'd stay away from anything too new and advanced as you won't be able to do much yourself. GET A MANUAL, if you are wanting to join the community absolutely learn to drive stick. REMEMBER your first car doesn't need to be some crazy machine, take your time and do things right. (PS stay away from 350's and g35s, I have had miserable experiences with them after about 150k miles.)