I have seen an automatic bobbin before but have not seen very many positive comments. The ones I have seen that liked it say it took a while to get used to using it and didn't like it for larger flies and materials.
As for fish hair, I have heard a lot of good things about it. By the pound COULD be the way to go but a wholesale company could be much better. I have used a little of it and I know I would not want to simply get a loose bag of it and try to use it in mass. I wish I could help you with a supplier but neither Hagens nor Lakeland had it in their catalogs. Might try Umpqua.
I love taking my kids fishing, now if I could just manage to fish at the same time.