if you are just making beats and recording vocals you can probably get away with a decent computer a small audio interface w and a midi keyboard w reason or FL. I've been rolling with that and an old ass dell from 2003 thats hella outdated, my reason beats are somtimes too much for it to handle if i have too many combinator racks and effects rockin.
if you are trying to record bands and running cpu intensive plugins you'll need a larger interface a beefier computer with some good ddr3 ram
how much money is in your budget? And what are you trying to do?
I'm looking at the Dell studio with that new intel i7 hyperthreaded quad core processor, that thing is a beast and should keep me cozy for no matter what i plan on doing running protools mpowered 8 with a M-audio project mix i/o. get yourself a focusrite octopre or another 8 track pre with ADAT support you have a fully functional 16 track studio. I saw a tascam 1884 for 500 bucks which is the same if not better than the project mix but i'd have to run a different DAW instead of protools they all do that same thing anyways
you'll also need some good studio monitors and preforably a sub to go with it, I have the mackie MR5s which are nice for a small project studio. it would be best to get a sub with those because they are already heavy on the low end, you wanna get a sub to cover the low end with those. KRK rockets, m audio BX series and Event TR series are all popular choices for around 400-500 a pair.
If your'e recording vocals you are gonna need at least one mic. Best choice for vocals is a large diaphram condenser a favorite choice of mine is a Rode NTK which is a vaccum tube condenser which sounds pretty awsome for like 500 bucks. Rode makes the best bang for your buck microphones period IMO. If you can find one a company called Aphex makes very solid clones of a Neumann U-87 and for around 200 bucks. If you can find them, i heard they were discontinued
check Ebay, gear orphanage and craigslist. theres always a good deal to be found on the used market if you know what you are looking for