Color can be one our strongest tools to help invoke an emotion or characteristic of a company for a design. So many times I see designers getting stuck trying to come up with the perfect color combination to fit the project. There are two tools I would like to pass along that will help in those wearisome decisions, one is the "edit" color window in Illustrator and Adobe's Kuler.
In Illustrator you can select the edit color window and you will get an window like above. From this window you can select a color and it will help choose those that go along with it by sliding around on the color wheel. You can then save and use in any project.
Adobe has a wonderful color website called Kuler. This site allows you to interact with color in several ways. First, you can take a look at the many color combinations that others have made and saved on the site. Second, you can go in and edit any combination making your own color palettes in the following ways; analogous, monochromatic, triad, complementary, compound and shades. You can then save or copy down the color numerals to use in your projects. The third great use of Kuler includes an option where you can upload or pick a photo from Flicker and pick colors from the image. Kuler will give you the colors and they you can save that for your projects.
I hope this helps you get creative with color on your next project. Now go crazy with color.