| Cakewalk | www.cakewalk.com |
| Carvin | www.carvinguitars.com |
| Casio Nederland | www.casio-europe.com |
| CDDB | www.gracenote.com |
| the Chordboard | www.chordboard.com |
| Citron Guitars | www.citron-guitars.com |
| C-lab | www.c-lab.de |
| Clavia | www.clavia.se |
| Coda | www.coda-music.com |
| Comex | www.comex-sales.com |
| Community Professional | www.community.chester.pa.us |
| Crateamps | www.crateamps.com |
| Crazy Notes | www.schizophrenia.com |
| Creamware | www.creamware.com |
| Creative Labs | nl.europe.creative.com |
| Crown International | www.crownaudio.com |
