music_guitar

Leper's Musical Circuits Archive: This is the first online collection of effects schematics, and probably the largest. Put together by Jamie Heilman
Guitar Related Circuits page -: This site archived most of the schematics from Jamie's site. There is a mirror site as well.
Aron Nelson's DIY Effects site: One of the more complete sites available
Robin Tomtlund's Site: Swedish schematics site - the schemo's are in English
Stellan's Schematics: Another Swedish site, good schematic collection
JD's DIY Projects for Guitar Players: Schematics and beginner information. JD has proven himself a good writer of this kind of stuff - AND he uses initials, too! 8-)
Plate to Plate: Tube Screamer and Fuzz Face mods, other schematics.
GM Arts: Articles on distortion, amps, a few schematics
Justin Philpott's page: Schematics and beginner info
Frank Clarke's Zone of Distortion: Mods for the Tube Screamers and and some others.
CJLectronics: A smallish collection, but schematics you won't find other places
Swap Site for Guitar PCBs: Some layouts for effects PCBs
Electronics for Music II and Tom's Synthesizer Cookbook: Primarily oriented to analog synthesizers, but with some guitar effects
Analog Modular Synthesizers: Primarily synthesizer circuits, some guitar effects as well. Most are in .pdf format and need Acrobat Reader to view them.
Paia Electronics: An old line effects/musical electronics supplier.

Books

Electronic Projects for Musicians by Craig Anderton
Electronic Projects for Guitar by Robert Penfold
...which outline not only the schematics, but how to read them and how to find parts, how to make boards and packages and boxes, etc. If you have no experience with effects, get one of these books first. In fact, get them anyway. They are very good references for people interested in effects.

Magazines

Guitar Player
Other schematics are available commercially in back issues of this magazine, where Anderton wrote an irregular series of articles starting in the seventies in which he would outline an effect and how to build it. Some of these are significantly different from or more flexible than commercial effects.
Others ...
Other electronics-related buildit magazines have published articles on the odd effect or two over the years. These include Popular electronics, Radio-Electronics, Electronics Technology International, Electronics Today, a little-circulated rag called Poly phony, and another called Electronotes (although the Electronotes articles are primarily oriented towards analog synthesizers).

Kits

PAiA
Effects kits are available from PAIA Electronics, 3200 Teakwood Lane, Edmond OK, 73031, 405-340-6300. It is useful to write these folks and request a catalog if you're interested in effects. John Simonton is the president at PAIA, and is on line at PAIA.aol.com, or was for a while.