The following information is provided as is, and the authors take no responsibility for the correctness.

Links

Links that are interesting to developers and engineers.

General

Printer Working Group: Various printing standards
Open Printing Workgroup: Standardizing on a Scalable Print Environment in *nix.
Cyrion Technologies: PCL and Windows Printing informations. Tools, Articles and Links
Parallel Port Central: A collection of files and links to material about the PC's parallel port, including ECP, EPP, bidirectional, and IEEE-1284 modes (and other I/O ports as well).
USB Central: Information, tools, and links to material about the Universal Serial Bus (USB).
eServiceInfo.com: Service manuals, electronic components datasheets and equipment schematics database.
LabMice.net: Windows Printer Management
QualityLogic provides software testing and quality assurance services, as well as test tools for driver and printer description languages.

Hollis Technology Solutions: DDKBUILD: (Free) Integrating VisualStudio™ with the Windows DDK build process.

WinPrnDev - Windows Printer Driver Development
This list is dedicated to the development of printer drivers and spooler components for the Windows family of operating systems. Looking for Win32 or user-mode peer support? Not here.
But if you've got a design, implementation or support issue with a Windows printer driver, this is the place to be - Take the opportunity to learn from your peers to get over that particular development hump.

Microsoft Printing, Imaging, and Fax Community
Print Services Testing: Windows Print Spooler stress testing with Microsofts WSSRA
Feng Yuan: Windows Graphics Programming: Win32 GDI and DirectDraw
The Paul Yao Company: The Paul Yao Company offers a course, “Principles of Windows 2000 Printer Device Drivers”.
PrintMirror: An EMF printer driver, with source
Bruce Sandersons Web: Printing, Windows 2000, Windows XP