Where to buy foam?

Thanks to all who gave great location advice to find the black iron and piping I wanted.

Now I need the foam. My hobby, or one of them, is making my own furniture. So, many kinds of foam from soft cushions to pillow fluff to high density to polyurethane, to general couch cushion is what I am after. Cushions mostly the next few months.

Anyone know of a good shop that will sell small-quantity retail?

Thanks!