Dr.Explain - Dr.Explain software is a help file authoring tool.
ManualsLib - Just enter the keywords in the search field and find what you are looking for!
WinCHM - Creating CHM file, Make CHM file, Web Help. WinCHM Pro - Help authoring software (CHM, WebHelp, DOC, PDF) . With this powerful tool you can not only create chm file from scratch, but also convert a set of existing HTML files to a chm file.
Manuzoid - Repository that includes user manuals for various products
Document360 - Self-service knowledge base software focused on SaaS Products & Enterprise Software Projects.
ManualAgent - Manuals and guides