Before I started scoring my musical, Grimhilda!, I bought a book on writing for percussion which a friend had recommended. It arrived as my Christmas present, and I'd no sooner got started on reading it when it vanished. After some months it turned up, in an obvious place, and I finished it...as best I could.
You have to have some sense of what percussion is all about to get the most out of the book, and in the end I stuck to a fairly straightforward set of percussion instruments for the scoring of Grimhilda! The young percussionist who played the music did very well with it...surpassed my expectations, in fact.
I was reminded about this while reading some advertising for Vater drums, made by Vater Percussion (as you might expect). They're instruments are top-notch by all accounts and the front page of their website has a list of the top musicians who have recently begun using their equipment.
To go back to the percussion book...some of the instruments written about I'd never heard of, and if I've actually heard them, I wouldn't be able to tell you. Many film scores these days use a lot of relatively exotic percussion instruments, so it's possible some of those that seemed foreign to me weren't, in fact. The book could have done with a CD on which there were examples of each of the instruments but I guess the publishers thought that might add considerably to the expense.
At this point I don't have plans for another musical, though I have thought about it. If and when I do write one, I'll probably have to go through the book again, though of course, it's all very well writing for exotic instruments. Finding the actual instruments in the city is another matter altogether.