David J. Stern may be the best-known beneficiary of the foreclosure boom, having made millions in recent years from evictions processed by his law firm, the largest of its kind in Florida. But when he took part of his firm public early last year, he had plenty of help from a constellation of investors also looking to cash in on people losing their homes. Early in 2010, the back-office processing operations of  Stern’s law firm were converted into a publicly traded company called DJSP Enterprises. Stern pocketed nearly $60 million from that transaction, public filings show. Behind that big-money deal was a curious cast of characters, including some with previous run-ins with regulators.