Aquamarine, Geko, Tauch Terminal and Spice Dive all gave good to excellent replies (if always a bit slow).
I went with Geko because of recommendations, very comprehensive replies and an excellent package over 4-5 days for 2 divers. All these outfits with the exception of Spice Dive perhaps, seem to have expatriate managers / instructors as you can see from the websites and email replies, AQ (GB), TT (D+?), Geko (GB + NL).
In the North we haven't decided who to use yet although Spice Dive are favourites !
By book I think you are talking about a course manual ? For OW or AOW (a lot of people take this after 10 dives or so - bad call Padi, personally I believe there should be a minimum number of dives logged, say 25 - 35 ) ? As Nusa Penida has some ripping currents (inc. down and changeable) then some experience is necessary.
You can buy the course manual separately if you wish - I think it was around 20 - 25 USD but I may be wrong.
I've heard fantastic things about both Menjangan and Nusa Penida (best two sites in Bali perhaps ?)- but completely different types of diving. Manjangan for it's incredible variety of life and superb coral growth, turtles and maybe pelagics, Nusa Penida for the pelagics, such as Manta, Mola Mola, Sharks etc. !
I'll be on the plane tomorrow and will let you know how it goes and if Geko are a good outfit - if I get a chance. Whatever I'm sure you'll have a great time !
Dive Safe
Kevin