Richard,
I recommend these books for ancient beads:

For Islamic Era middle eastern beads traded to Africa: Middle Eastern and Venetian Glass Beads by Augusto Panini.

For a scholarly work on Indo-Pacific beads, 300 B.C to the present: Asia's Maritime Bead Trade by Peter Francis, Jr.

For a book based on the Ulrich Beck collection of ancient beads: Magical Ancient Beads by Jamey Allen.

These books can be very expensive to purchase - I suggest checking Amazon and ABE Books periodically, as well as eBay, to see if you can get a reasonable price on a used copy. The Francis book normally is available for under $50 but the other two are running $200 - $1000 right now.

Best of luck as you embark on a fascinating endeavor!