Buy.com HAD 2000 'super points'($20 credit) for about a week when buying from them, but that's gone now I believe.
Best bet would be to stalk your local GS(or Hastings) stores and wait for a B2G1 sale on used and hope to snag a copy with two other titles. Otherwise most sites only have $2-3 off MSRP right now for 'deals'.