A new version of the LaTeX Songs package is available at <http://songs.sourceforge.net/>
More options are available for indexes.
Would be nice to integrate.

Beware: patch for gtab delimiter:

< \newcommand\SB@ctoken{} \def\SB@ctoken{,}

---
> \newcommand\SB@ctoken{} \def\SB@ctoken{:}