I think you're getting a lot of good advice. The "no RWD" requirement is unfortunate, I had a RWD Chevy 1/2 ton pickup with the V6 and a 5spd manual as my first car, and it was a great lesson in car control, especially going to college in upstate NY, where plowing was seen as an optional activity.
I had a '98 Camry (4cyl/5spd) shortly after that truck, and a few minor mods really transformed that car (Whiteline F&R swaybars, Eibach springs, KYB struts, and a TRD Quickshifter). I think the suggestions of small, FWD cars are good ones. Although not as much fun as RWD, FWD isn't a complete disaster with a little bit of work. Get insurance quotes before you buy - I had my heart set on a Nissan Maxima 5spd, but the insurance was almost double the amount of the Camry. Insurance can be a bit counter-intuitive as well, my parent's '94 Corvette was about 1/2 the cost of their '02 Mustang GT, for example.
As Keith mentioned, I'd choose reliability over outright speed and sporting potential at this stage in your driving career. And echoing what someone else said, in your price range I'd buy condition over the perfect theoretical make/model. Getting some time with autocross, a performance driving school, or a Tire Rack Street Survival event would be a great idea.
Some options to think about later down the road:
BMW 3-series would be another option if RWD was in consideration, although they do make them in AWD (but they're more complicated than the RWD models). BMWs tend to be time-consuming/expensive to maintain, so that might be a better choice later on. I had a '96 328is (Sport Pkg, 5spd) that was a lot of fun to drive, while still being a very comfortable cruiser.
Saabs have a lot of potential, we had an '00 9-3 Turbo that was improved with a Genuine Saab rear swaybar and a front rack steering brace. The automatic was actually a good fit with the turbo, and the sport mode on the transmission made a bigger difference than in any other vehicle I've driven. They're not sought after right now, so the costs are low. Parts availability might be a question mark, but they made enough of them that I think you'd be fine for a while.
The G35 from '04 and up is a very capable machine. If you can find one that was taken care of, the 6MT package with the Brembos is a great car. All the performance of the 350z, with a cloak of invisibility, and a longer wheelbase that makes them more stable than the 350z (some might say less tossable, it's all a matter of perspective).
Good luck with the search!
EDIT: Looked at the local CL quickly and two other thoughts popped up - the Toyota Matrix/Pontiac Vibe with the 2ZZ/6sp and the Acura TSX with the K24 and the manual.