How to change color of an image in Illustrator?

To be perfectly honest, I'm not at all familiar with this, but I do know where it is (I've probably used it all of one time). You may be able to figure it out on your own or you'll be able to Google for a tutorial because you'll have the name!

You select everything, then go to the Color Guide (from Window pulldown menu or menu on right side. You can select from what's there or use the pulldown at the bottom left corner. I'm sure you can also customize somehow - either at this point or the next step. Hit the little circle at the bottom of the palette (Edit or Apply Colors). This is where I think you can do some serious editing. Then hit okay.

EDIT: Oh crap, do you really just want to change the color of an object (I just read Laura's answer). I thought you wanted a global color change to all the elements. I think Laura's right - that's all you want to do. Oops. Ignore my answer. Though I'm leaving it up because it's a very cool Illustrator trick!

Use the black arrow selection tool and select the thing that you want to change the color of. Once it is selected you can use the standard color selection box to change the color.

Thanks for the help. Your suggestions have worked :)