OK, so I've gotten into painting my own car, so far I've done the front bumper, hood, and the back of the hatch/spoiler... I've bee doing some reading and all on painting cars, and I keep hearing that you can use 1500 grit sand paper and wet sand your paint job and simply buff/wax it out again to a shine... I never thought that would be possible! Wouldn't the sanding leave your clearcoat all messed up and bad looking??

not at all, in fact the paint shop will sand it down and buff it before a customer picks it up, sanding is what give a dry paint that "wet look"
What you want to do IMO is use 2000 grit and wet sand it, use a liberal amount of water, you never want to sand it dry!
So anyways just start with the 2000 grit and buff it out with a good compound from 3M or what ever brand you prefer. The catch to buffing is you need to get a good rpm going, you can do a ok job with just your hands but a actual speed buffer will get the smallest scratches out. Good luck man i hope i could help some.... and im sure someone has something on top of what I said that can also help you out like what rpm you want your buffer at and so on and so on.

Yeah you don't want to run a high rpm on the buffer, cause you will burn through the paint if you leave it in one spot, always keep it moving. I think its between 1200 & 1500 rpm, not to sure about it so double check. Also don't let the bufer STOP on the vehicle. Hope some other people have more input than us. Good Luck

like posted above wet sand with 2,000 or more. we use 3000 at work after a quick dry sand with 1500 but i wouldnt try it with a grit that high for a novice. then use a rubbing compund with a wool or foam pad , 3m makes great stuff. after compound i would use a fine swirl mark remover with a black 3m pad and then a ultra fine swirl mark remover with a blue pad. afterwards i would wash the car really well to get all the compund and stuff off the use a hand glaze. if you go to a paint store and ask for everything you need they should be able to hook you up.