Ok -- I've confirmed the first 2 links for some unbelieveably wonderful fiber-sellers in the US.
Roclans -- Kate grows the most unreal Ramboullets you'll ever see! And her fiber is worth emailing and ordering. She dyes the fleeces then has them processed for spinners -- the result is the softest, most wonderful spinning fibre you'll ever feel. Well, I'm biased, as in addition to having great fiber, Kate is an ACE person and so is her husband, who runs the farm and keeps her Rambos in good shape. Email her and ask her what colours and types of fibers she has in stock. It's worth the extra effort.
Flying Fibers: Jeri stocks rare UK sheepwools. I've stashed a variety to take back home with me. I'm particularly taken with her Manx batts. They're so kewl. Jeri is a talented fibre artist -- and I now am the proud owner of one of her wild hats -- PURPLE of course! I love it so much that I'm sad it is summer in Oz and can't wear it for a while. Buggah!
I'm sorting through what I've hoarded and will post more links as I get to them.