My desk is 36" deep. In my day to day operating area it leaves plenty of room for a keyboard, paddles, logbook, notebook, etc. I tend to keep my operating area very clean and uncluttered. My main rig is at table level. The rest of the desk has a shelf/riser 18 or 20" deep (built for boatanchors..). All of the desk framing is 2 x 4's or 1X2's for the shelf framing. Everything is very sturdy. Not pictured but at the same work height is a workbench to the right of my operating position with three tiers of shelves filled with test equipment.
Here... 2nd pic down in my bio:http://www.qrz.com/db/KB2FCV