Hey Jim,
My desk has deep drawers to. I picked up some filing dividers from Staples. I screwed them down to the bottom of the drawer. Works great for standing hackle up, hens, really anything stapled to card stock.

I also picked up some desk drawer organizers. All those little squares are great for tied flies, and the larger areas are good for materials. Keeps them out of the way and close at hand.... at least for my clumbsy hands.

-Gregg