Finding the right colors is made easy by W3Schools' numerous color libraries. I have used them so much that I decided to organize them in a way that makes choices easy for my clients, and demonstrates exactly how their choices are rendered online.
Don't forget about the 140 or so colors recognized by name on every browser listed at w3schools for a great selection of neutral and light colors for backgrounds.
When using color in design, it is helpful to understand the trends, traditions, cultural symbolism, psychology, and emotions tied to colors. The color palette you choose can affect the user's attraction to your site, length of visit, and confidence in doing business with you.