Webpage background advice needed

So Im working on the background of my website trying to mesh colors and such… however I have run into troubles and need a small bit of advice if possible..

http://ezeshops.com/ is my website, for reference.

How do the pros out there pick colors for the background that match, is there a tool to make the textured background to the color you want, and what colors would you recommend for my site.

2nd … I have a div for the header a div for the footer, and a body background…. is there a way to move that header background up slightly so its halfway in the menu without screwing up my shadow effects? Im guessing absolute positioning but figured id ask first

The biggest issue is the colors though, I suck at art and cant find a color combo that looks good that have a background texture that meshes well.