Subud books can be purchased online at By the Way Books
Some Subud authors publish their own books and sell them independently. They can be found at www.subudbooks.com. In addition, if you have a tablet reader this site also has many 'Subud Classics' in the e-book format.
Subud material may also be found at the Subud Library: www.SubudLibrary.net (Talks by Bapak and Ibu Rahayu password protected).