There are a few places to get Luxeons. Prices below are for Luxeon I Stars price is for 1 unit.
theledlight.com $13.50
luxeonstar.com $10.88ish
lsdiodes.com $10.20
ledsupply.com $9.99
theledguy.com $9.00-13.00
I'm sure I missed some, so if others know of some that I missed post em.