Most of my patterns are designed so that you can change the colors up to suit your style and decor. But if you are feeling a little stumped or color-challenged, here are some places that I go for a little color-play and inspiration.
Felted Button on Pinterest -- I consistently pin color inspiration here, especially on my "Colorful World" board.
Colors on the Web
Random Stripe Generator
Granny Square Color Pattern Generator
Color Scheme Designer