Where can I buy loose gems?

I would like to purchase GREEN AMETHYST, MORGANITE, & KUNZITE. With the exception of green amethyst, I've never seen any of these gems used in the tangible marketplace--I mean, I've never seen a kunzite pendant at Macy*s or a morganite ring at Ben Bridge. I've only heard of and seen morganite & kunzite on GemsTV. I'm wondering where I can buy these as loose stones, OR as already made jewelry pieces? Any information would be greatly appreciated :)