I was asked the other day if I knew of a DNN document library with version control. At the time, I didn’t, but I’ve since found one from WillowTree Software.
This is a DNN 3.1.x or later version of the Wrox Document Dontrol (DNN ported) module. This was first offered by Mark Hoskins (KodHeaz), then Robert J Collins (WillowTree Software), then Tam Tran Minh (TTT Company), and lastly (and once again) Robert J Collins (WillowTree Software).
Find the module at http://www.willowtreesoftware.com/Solutions/DotNetNukePortal/FreeModules/tabid/156/Default.aspx.
You can’t beat the price—it’s free!