If you are interested in partial wool felt, then
Prairie Point Junction has great prices. While I really prefer to work with 100% wool, the blends are half the cost, so much more affordable and still way better to work with than acrylic felt.
I also like
felt-o-rama. They have wool felt, blends and bamboo felt. Great color selection. And
Weir Dolls has good prices too on 100% wool.