Here is some silk thread from Artbeads, one of my favorites for good prices and no shipping costs
http://www.artbeads.com/searchresult...xt=silk+thread
and of course, a great supply house, /fire Mountain beads. In this case Artbeads has the better deal.
http://www.firemountaingems.com/shop...ORDGUDEBRODMHW
Also try googling silk bead thread or punch it into Froogle:
this is the page of results I got. Lot of BIG spools from ebay for 12.95
http://froogle.google.com/froogle?q=...=1&sa=N&tab=wf