KENNY-
the above advice is good. i have had the 'dirty sock' smell too (and my socks/feet weren't the culprit!lol)...
two things i recommend,
one is frigi-fresh, by BG products, OR any antibact. LYSOL will work, but not as well)
the other is to check your evap. drain tube. if it gets clogged, the mold spores willl grow activaely..... the way to unclog the tube is to use a hi-press (like the pump used to inflate your tires) air source, and shoot a blast into the draintube end.... you could also try a shopvac to 'suck' any blockage out,but i dont know if that'll work (need a funnel attachment for sure)
make sure you are getting the 'drip' on a reg. basis under the car, which is the condensation clearing.... then follow that drip upward, and you've found the outlet tuve....
good luck; its a pretty easy fix to a common problem...
eSE