In any case BB isn't for sale anymore, and neither is the manual and the product was given away on magazine coverdisk. In the absense of official support i'd think your ok to help Jim. :)
Amiga Blitz was officially released under the GPL several years ago, as AmiBlitz (you can download the 68K Blitz compiler source, as well as the full distribution, on the Archives page):
http://www.blitz-2000.co.uk/
There's also a more recent distribution here on Aminet.