estarland.com has used PS2/NGC/Xbox games and accessories at a "buy 1 at full price, get the 2nd cheaper item for 70% off"
I got 2 dual shock 2's for about $23, but I have to return one because the L2 & R2 triggers are broken -_-
Mixunit.com has Sony-brand 8mb memory cards for $10 and its like $4 shipping - I bought 2 and with shipping, came out to be cheaper than buying one at a store and paying tax.