Check out the Fishman MIDI interface:
http://www.sweetwater.com/store/detail/TriplePlayPUThis is a MIDI controller that should work with BiaB.
If my old Casio Strat MIDI controller ever dies this is what I am going to get. I will attach it to my guitar but if I get rid of that guitar I will pull the Fishman out and put it on another. It looks like this is very cost effective plus it is getting very high ratings.
Good luck.
PS – but be forewarned that you have to be very meticulous when playing a guitar MIDI controller. Strumming open chords can lead to false readings. Also be prepared to do a little MIDI editing. Cleaner playing will yield the best results.
Think of playing a guitar MIDI controller as a new instrument. It takes a little time to learn what you can and can not do.
Been there – done that!