Mellotrons and Optigans
J.P. Hovercraft's Sample Page, Mellotron, Mellotrons, Chamberlins, and their Sounds, Optigan and Orchestron, Optigan.com, Streetly Electronics: the original Mellotron maker
MIDI Controllers
DIY, Body Synth, Buchla and Associates, Buchla Lightning II, Chordboard, Controller Zone, Digital Dance System, Gulbransen, Inc., IBK, Infusion Systems, Kenton Electronics
Synthesizers and Samplers
Akai, Alesis, Clones and Emulators, E-mu, EMS, Ensoniq, Generalmusic, Kawai, Kits and Plans, Korg
Theremin
Performers, Art's Theremin Page, Jerry's Tube Theremins and Trautoniums, Levnet -- Friends of the Theremin, Maxies Pages, Moog Music, The Musical Saw and Theremin Page, Theremin Enthusiasts Club International, Theremin World, Theremin.info, Thereminvox.com
Vocoders
Software, Analog Vocoder information, Doepfer A-129, Electrix WarpFactory, Korg MicroKorg, Korg VC-10, MAM VF 11, PAiA Vocoder, Roland VP-330 Vocoder Plus, Vocoders and Vocoder-Derivatives
120 Years of Electronic Music
Listing of instruments from 1870 - 1990. Includes an introduction, bibliography and links.
Electronic Musician
Articles cover technical information and product reviews including home recording equipment, drum loops, and audio samples.
Music Electronics Archive
Schematics for some commercially available synthesizers and effects, electronic musical instrument links.
Synthtopia
Electronic music resources. Features forum, news, interviews, music and gear reviews, artists, directory, and downloads.