here ya go:
http://www.dealextreme.com/details.dx/sku.2941
A set of 4 for $3.54 shipped. 3 colors you won't want, one color you'll love. (PM me if you only want the baby blue one, I'll send it to you for free)
I order from DX all the time, takes about 2-3 weeks coming from overseas. It's the only stylus I use, it's retractable, and fits in the DSLite slot perfectly. I've been using the same one for over a year now. Other than that I'll let the reviews speak for the product: 4 out of 5 stars with 110 votes.
While I'm sending you there, check out all the other weird crap they have, it's some of the craziest things I can't seem to resist: most recently a life-sized cooked shrimp cell phone fob, miniature sushi plate, and a mini Domo-Kun screen cleaner/keychain/finger puppet...Nothing's funner online than browsing there in the middle of the night.
I also feel obliged to mention everyone's favorite: The Pig LED Flashlight...
For $1.18 shipped, every home in America should have a piglight for emergencies. (I forgot to order another one for myself recently after a visiting friend's son "accidentally" took it with him when they left)