20k There is quite a few to choose from.. I was just going over this with my friend..
Check road and driver, they just had a review of cars under 25k
And suprising the Mazda MP3 got really really good review for handling..
My sugestion, get an Mitsubishi Lancer, for about 16k loaded and spend the other 4 grand on mods.. A turbo would cost about 1k, and give you a lot of power.. Its not AWD, but its a very tune-able car and its looks really nice...
Read up on, go to the book stores and get some car mags. Educate yourself and make a wise buy!