well, i'm on fleabay and saw this:
http://cgi.ebay.com/16-CH-Power-Supply-CCTV-Camera-18-Port-12V-DC-Pigtail-/320557376729?pt=LH_DefaultDomain_0&hash=item4aa2b564d9#ht_1902wt_1140
"Output: 12V DC, 12A Terminal Connection
Max Draw: 20A"
so I am guessing that my computer power supply might actually work.