I agree with Jaxxhits. Find a nice computer with at least two gigs of ram that is known for its performance. I personally love only on macs now. If you want to keep your set up relatively cheap then heres what I would suggest you buy and why. I'm listing these things assuming that you already have a computer that your going to be starting off with. Get
reason 6 (399.99)
Reasons has beat creation and a vocal recording and mixing program in one. Your going to also need a midi controller...the axioms are pretty good (299.99 for a 49 key) If your really hurt on money you can get a plain radio shack 100
Casio and just use it for the midi out
Now you could use the speakers that came with your computer but its never going to produce any good representation of what the music actually sounds like(as it relates to other top grade monitoring systems)
So with that being said, in order to get some descent monitors your going to need a way to plug in their 1/8 inch jack or XLR cable. This means your going to need a sound interface...I just anything in the 200-to 500 range. What you want to make sure is that you have atleast one set of monitor outs for your studio monitors. Midi in and out is a must. But as long as you have those then you'll be pretty good.
Studio Monitor wise...I suggest
the Rokit 5's (299.99)
So your looking at a rough grand total of (minus pc) $1300 give or take. It can probably be alot cheaper if you buy used from like pawn shops or ebay.
There are a ton of youtube tutorials out there that show how to make tracks using propellerhead reason. You want to make sure you have a descent understanding of midi and proper monitoring. I hoped this helped...let me know if theres anything else I can answer for you