1000BiT: Old computers manuals.

Altair Manuals: The following links are scans of original Altair, CP/M and other manuals in pdf format. Most manuals are searchable.

IBM 51xx PC Family Computers: This web site is intended to be a reference for computer-savvy people who are already familiar with the IBM 51xx PC family of vintage computers. This web site contains information that ranges from basic to very technical.

IEEE-696 / S-100 Bus Documentation and Manuals Archive

Manx: Manx is a catalog of manuals for old computers. Manx is an open source project hosted on CodePlex. This catalog mostly covers manufacturers of minicomputers and mainframes, or associated devices such as terminals and printers.

Microatena (ITA): Elenco libri e manuali

PDP-11.RU Mirrors Archive: A large archive of various mirror sites and consolidated information on retro computers.

replacementdocs: Have you ever rented a game that came with no instructions? Have you ever bought a used game and found out later that the package you received didn't come with an essential map or answers to copy protection questions required to play the game? Have you ever bought a re-released game and then realized that they only included an Installation Guide, no game instructions at all? Has your wife (or husband!) ever just thrown out all your game manuals because they thought “you didn't need them anymore”? If so, replacementdocs is here to help! We're here to provide you with those manuals for situations when you really should've had them to begin with.

Tim’s laptop service manuals: In the same vein as in my driver guide, I’ve started finding laptop service manuals and hosting them on my site. These are the professional, official documents published by the various laptop makers, either for their own technicians or for the use of the general public. They generally detail the exact list of parts in each model of laptop – often down to individual screws, if you happen to have lost some and need to know the exact size for a replacement – and describe the procedure for disassembling and reassembling the entire machine, including panels, RAM, wireless cards, keyboards and touchpads and LCD screens, all the way down to the motherboard itself.