This is my documentation hotlist for my Apple II interests:

• ProDOS
  • ProDOS 8 Technical Reference Manual
• Apple II Technical Notes
  • File Type Notes
    • ATINIT and Printer.Setup
    • EasyMount Document
• 6502 Resources
  • 6502 Opcodes
  • 65C02 Opcodes
  • 65C02 Opcodes Matrix
  • Western Design Center
• AppleTalk
  • Inside AppleTalk, 2nd Ed.
• Apple II Technical Reference Manuals
  • Apple //c (with ROM $03 listings)
  • Apple IIc, 2nd Ed. (with IIc Plus, no listings)
  • Apple IIe
• Apple II Documentation Project
• Schematics
  • Apple IIc Plus Schematic