What we all should be looking out for is the supercharged corvette coming out! That thing is going to be sweeeeeeet! But I hear what you're asking....I'd say in about 4 years you could get one for about 30K. Remember though, when you buy them used, they will be abused! You can always spring for a Lingenfelter engine though which comes with a warrenty. That'll put you back up in the 40K bracket but it'll be well worth it....the power will be as much as the Z06.
Check out the current prices on '03 models. You could get a pretty good idea of how much it would depreciate in 4 years. I have no idea what you're asking about automatic clutch.