0-60: My advice is that you build a new computer yourself (exclusively for music). I built one two years ago, and there's not that much to it if you have access locally to the parts and you have a knowledgable person helping build it. Here in San Diego there are hundreds of computer stores competing for our business, and you could build a kick-ass machine for under $1,500. Example:
ATX Mid Case = $25
Abit BE6 = $135
Athlon 500 = $195
128mb PC133 SDRAM = $140
IBM 7200 RPM 20gb = $180
SB Live! Value = $55
Super Drive = $50
Video Card = $50
48x CD = $50
CDRW = $200-300 (a good one)
17" Monitor = $250
Total = $1,430 + tax
If you forego the SB Live! and share the monitor with your regular computer, you could afford a truly great sound card, although the SB is terrific for the price.
Buy the parts yourself, and pay somebody you trust a hundred bucks to put it together. I actually paid a dude $100 just to show me how to put it together. He also installed the operating system for free. I'll also bet you can find a free copy of Windows 95, 98 on NT if you look.
Keep the Crapaq for Internet and writing letters to your great aunt. You'll never get any $ for it.