I have it though the last time I did much with it was a few years ago. It tries to cover mainly OS based things but it is very Workbench 1.2/1.3 centric and a number of the ways it shows you to do things are not necessarily the best way to do them.
Book wise, for OS programming, you are probably better off looking at the Paul Overaa books. For HW programming, the ROM kernel manuals would be the better way to go. I found the Paul Overaa intro Assembler book a good start as it covered a lot of the 68000 basics better than the Abacus book did.
I was also lucky and knew a few people who did assembler so was also able to ask them for advise at times so don't discount that either if you are interested in learning 68k asm.
It's been a long time but and I have had a few drinks but
moveq #0,d0
rts