Out of curiosity...

Just right off the bat, how much would a Nintendo Gamecube with a wireless controller, all cords, and the following games (StarFox Adventures, Spider-Man, Harry Potter and the Prisoner of Azkaban, Pokemon Colosseum, Viewtiful Joe, Zelda The Wind Waker) go for?

Check Ebay.

Conservatively... about $60 or $70 at a yard sale, maybe $100 on Amazon/Ebay, or between $45 and $90 at a used game store depending on how much they'd sale the games for, the percent of the price of the game they give to customers for trade in, and whether or not you take cash or in store credit.

probably $30. but even at that price, i wouldn't buy it. there comes a point where something just becomes unsellable.

I think you'll have a hard time selling for more than $60. Ask 60, be prepared to negotiate to 45, and you'll find a buyer