Below are links to user forums and businesses offering parts and services for antique radios. 

Antique Electronic Supply

Nostalgia Air (Schematics, Online Tube Reference, and Forums)

Just Radios

Radio Daze

Renovated Radios

Mouser Electronics

DigiKey Electronics

Online Components

Philco Radio (Philco Information and forums)

Philco Repair Bench (Philco Radio Informaiton and Schematics)

Antique Radios (Radio informaion and forums)

Play Things Of the Past (Lots of radio parts and Tubes for sale)

Broadcasting History Guide