cheapest is go to zellers, buy a ubisoft game for Wii at $14 (some onsale now, just bring to the counter and scan it), then trade the game to EB games, with this trade, you can get a NDS for $99.
btw, that $14 dollar game also qualifies for by 1 get 1 free as well. enjoy.
New LYK is not user friendly and is annoying. Now you can blow me.