Ben Heck has made a lovely job on making Guitar Hero more accessible for gamers unable to use both hands to play. It’s not quite a D.I.Y. guide that he’s posted on his web-site, but there’s enough to get going with for some. Daft video here.
Guitar Hero for one handed play - IGDA Game Accessibility SIG
All about accessibility, founded in 2003.
Looking for pedal to use for guitar hero/rocknand
I had a stroke and can no longer use my left hand (hand to strum