I have a working (at least, plays back MP3s properly) Allegro-1 / Maestro3
driver ready to go for anyone interested:

 http://invisible.yi.org/~jmcneill/netbsd/esa-20010826.tar.gz

Please, beat on this as much as you can. I would appreciate any feedback
that anyone would like to give me.

Special thanks to Peter Seebach for supplying me with the hardware to test
this on, and Antti Kantee for helping me out with the FreeBSD -> NetBSD
conversion.

Enjoy!
Jared