I have a ferret. He is in my avatar. I suggest using petfinder, goosemoose, and craigslist (search 'pets' under community or 'pets' under services...occasionally there is a free one under 'free'). I don't know of any breeders, and I have never heard of one that breeds for color particularly. I think if you search around enough you can find the color you want. My ferret (Hobbes) came from a pet store, and if I ever got another one I would adopt. Just because I know more now about the conditions he was bred in. I highly suggest picking one based on personality and health, but I understand looking for a certain color if you're considering other factors as well. I wasn't looking for any certain color at all, but Hobbes happens to be nice looking and have a wonderful personality PM me if you have any ferret questions, but I'll try to remember to check back on this thread.
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After a time, you may find that having is not so pleasing a thing, after all, as wanting. It is not logical, but it is often true.
--Spock