Try this site for a map. Not sure if it has what you want.
http://www.maps-charts.com/webdoc1.htm
Lots of sites with pics of bunkers. Try this one
http://www.atlantikwall.net/anatomy.htm
You can google Atlantic Wall, Omaha Beach Bunker or something like that.
I have a nice book with some good cutaway drawings that I plan on using. There were also several Tobruk bunkers which are pretty easy to find on the market. Tracks N Troops carries a couple of lines with just about anything that was there.