Here’s a few to start with. I will be adding more files, documents and ebooks soon.

ACE-HF System Simulation and Visualization software (for propagation)
ARES Field Resources Manual
CHIRP is a free, open-source tool for programming your amateur radio
Current Question Pools – All The Questions And Answers For Technician, General ANd Extra Exams
FEMA Course Manuals: Student Manuals, Instructor Guides And Exams
“Find PDF” – Interesting Collection Of Books And Documents About Ham Radio
G3VFP Compilation Of Ham Radio Software Downloads
Hamsoft – Linux software for the Ham Radio community
K6SGH Amateur Radio Software Links
KG-UV Commander (Programming software for Wouxun UVD1P, UV2D, UV3D and similar radios)
KSM Version 2.4 (Kenwood Smart Memory, for programming rigs)
N7QVC Files, Manuals And Documents
Prolific Drivers and Information (See also “Wouxun”)
Voluntary Listing by San Diego County CERT Teams of the frequencies they intend to use for drills and activations
Wouxun Prolific Drivers and Information