Anything by Freppo is a good place to start for this kind of stuff. Really good bloke who freely shares a lot of interesting stuff Including the schematics and often a stipboard layout on his own blog
http://www.parasitstudio.se/
He also sells PCB's there at a reasonable price and das musikding sell full kits as well
These layouts are already on here, just seach for parasit and you'll easily find them as well as plenty of other useful stuff