-The Duke Nukem Universe is one of the best duke pages on the net! This site is updated regularly and has many cool things on it including rated maps, duke poll, user maps, duke sharware, cons, rts's, and his own levels.
-This site is the LARGEST duke site on the net! It has a HUGE, I mean HUGE selection of maps (single, co-op, dm,). It also has a TON of cons, rts's, build utilities, duke launchers, links to tons of duke TC's and more. a HIGHLY reccomended site to any duker!!!
-This page is a must look for anybody who makes rts files, builds duke levels, edits cons, or works on a tc. It has all of the files, FAQ's, maps, utilites, patches, example maps, and dowloads that you will ever need to help you out with duke editing of every sort! This site has alot very rare files (upon looking there I found 5 files that I had been looking for quite some time). So what are you waiting for? Go take a look at this site!
-This page came out at just about the same time as mine did. It features only the best maps; single, dm, co-op. I would say about 80% of the maps on his site are REALLY GOOD. Again a MUST for serious dukers!
-This page specializes in bugs in Duke Nukem but has ALOT of other duke things. It has strategies, some good dm and singleplayer maps, great con hacks, build help (and other stuff), secrets, and all of the duke cheats. Another GREAT Duke Page!
-This page specializes in maps, both single and multi play. He has alot of good single and DM maps there, all rated very well. There are also some TC reviews and he has made some TC's himself. An pretty good page overall.
This page is really something, the creator of the site many made a handful of fun and creative duke maps. His site is very well done. He maps are all categorized into "themes" for easier navigation and he has alot of good duke maps. Definatly check this place out!!!