Glad you enjoyed the book. DRAGON'S TEETH is still in print, to be found in fine bookstores everywhere. ("Fine bookstores" being defined as "bookstores that sell my books", of course . . .)

The earlier stories are all out of print, although that doesn't affect finding them in a library. And if you want to track down copies on the internet, various places have them used or I have new, signed copies available through friends who run an on-line bookstore.