valve cover gasket

alright my cars leaking oil like crazy, i need a new valve cover gasket what do i need to look for and what exactly do i need to buy if someone could help me out send me a link or something its my left gasket as if u were standing in front if the car looking at the engine, it leaks oil like crazy, i need to knwo where to buy one and quick so i can get it changed, and do i have to pull or tilt the motor to change it, if so im gettin a professional to do it. i knwo i need the gasket i looked on subaru parts.com and it said left rocker cover gasket(aka valve cover) would this be all i needed to order was that gasket or do i need other things to. please please let me know im keeping oil in the car and doing all i can do keep from having to replace the engine, i dont really feel like doing that i bought the car for 1100 and ive put nearly 3000 into itfixing it. and its gettin ready for a make over(paint job) please let me know what i need im seriously desparate