Room is gonna be 10 X 10 give or take a foot or 2 on each.  Price isn't very concrete, I can see spending maybe 400 total.  If the parts are Sony I could probably get them at a decent discount, maybe 30% cheaper or so but they would have to be new.
I think 
THIS  is what my dorm layout is, I'll be in the single.  Although I think I am getting a loft so my computer can go under my bed.
And I have an iPod, so something that I can plug into that or my computer so I can play all my .mp3's would be ideal.
I was looking on ebay for shelf systems and 
this one  and 
this one  looked like good deals, if I really am willing to spend 400 I could prolly do better though.