I don't know any songs about Algerian Corsairs, but I do know a novel; "The Sea Hawk" by Raphael Sabatini. It's available as a trade paperback, with a preface by Bernard Cornwell. Sabatini was no Patrick O'Brian, but his historical novels are fun. The Sea Hawk does indeed raid Cornwall, to abduct his brother, and his erstwhile ladylove. He has them both sold into slavery. No one wants to buy his brother because the skinny boy wouldn't be any good for physical labor. That there were other uses for skinny boys wasn't mentioned in Sabatini's time, at least not in polite circles.
I know two songs about convicts who became slaves in the Americas. I believe the one is called "Virginia" and the other, a recent piece by a local singer is called "It's a Hard Row to Hoe".