As far as I know Andy has not written a new book "specifically" on the Sovereign GT or any Sovereign for that matter (at least not like the dedicated books he wrote for the Explorer or Quattro i.e., Mastering the Explorer, Mastering the Quattro) Closest thing I know of is his recent field test in the July issue of Lost Treasure magazine
http://www.losttreasure.com/FieldTests/ArchiveView.cfm?ID=LT20050724
In fact I don't believe anyone has written a book "specifically" for the Sovereign. As far as I know all the books on Sov also include the Excal and then differentiate between the two in the text (e.g., operating without the Notch control)
All the more popular Sovereign related books are now out of print but can be found if you look around:
1) Otto Feilers and Mike Keeners "Finding Rings with Minelab Sov and Excal"
2) Dick Noels "Tips for Success using Minelabs Sov and Excal"
3) Andy Sabish "Treasure Hunting with Minelab Metal Detectors"
4) Andy Sabish "Treasure Hunting with Minelab Metal Detectors Vol 2"
My biggest complaint is most books are written for either the Novice (which bores the seasoned user) or are written for the Advanced user (which leaves the beginner in the dust). I'd like to see a book that starts out with the basics. Has a complete glossary all all Metal Detecting terms, explains the principle and function behind all the controls and settings, and explaining things like falsing and null. I had a guy call me last week because he read a post that said he should be aware when his unit nulls. He asked how is he supposed to know when he doesn't know what that means. I got him back on track... (FYI... he doesn't surf the net
)
Yes... via the net all the information is available but some people like an all-in-one hard copy reference guide as opposed to searching the net in frustration.