There is a story in 'Chicken Soup for the Soul' called 'Willing to Pay
the Price', which is about a guy who came to the USA with nothing and
became a millionaire.

I am looking for similar stories about people who have gone broke or
bankrupt and ended up becoming financially wealthy (and how they did
it).

I found some at 

http://www.solvency.org/storiesindex.html

but want more.

There was a guy in the UK who went bankrupt several times before
striking it rich with non-iron shirts. He ultimately called himself
Harry Rael Brook and marketed his stuff as 'Rael Brook Toplin - the
shirts you don't iron'.