I'm glad to hear that others were able to jump on this also.
We sold back my DSlite to Gamestop yesterday, they gave us $30+$25 extra credit for a promotion they're running so I was going to apply that giftcard to a DSi from there, but I think buying this one from
Amazon and using the gift card for games from Gamestop is a better bet.
As for Target, I've been able to take items I've ordered from the website to my local store for return. You should be able to take your unopened white DSi with the shipping information and get the money refunded to your card.