Background tracks...

Here is a large archive of simple accompanyment tracks for old standards, courtesy of jazz guitarist Ralph Patt:

http://ralph.dinni.net/index.html

Perhaps there are some songs here that a theremin player might enjoy playing along with. In any case, best wishes.


Thereminless

I've also just recently dicovered that Hal Leonard produces a series of music books/tutorials with an accompanying CD of music with and without voice/piano/sax/whatever.

The trick is finding a retailer that actually stocks them.