I have 3 sealed game that I don't know what they're really worth.

I have Sonic Mega Collection Plus for Gamecube sealed (Yellow label)

Killer Instinct for Snes sealed

Paper Mario TTYD label sorta sun damaged sealed (Yellow Label)

Can take pics if you guys want to see.

Sonic - $23
Killer Instinct - $70
Paper Mario - $63

At least, that's how their labeled on VGPC.  I'm sure the ones that are faded or damaged will be worth a bit less.