So I want to add a background shadow to the main content box. I can do this in CSS, but I'm trying to lay out my site in photoshop first.

I can't do a simple drop shadow because there will be angles to it, and thats not what I want. I simply want a shadow vertically bordering main content area.

Maybe there's an easier way to do this in Fireworks?

I really wish there were more photoshop layout tutorials for flexible layouts.

Nevermind. I think I figured it out. Alternative methods are MORE than welcome though.

I used the marquee tool to select the edge of the content box, created a new layer via copy, then dropped the shadow.

I use a layer mask to create shadows, just use paint bucket and then add a layer mask, add a black/white gradient and you will have a nice equal shadow!