Chek-Mate Crusader--the same Crusader has been my favorite for the last 15 years or so. They have been going strong for 40+ years, with the bowyer of almost 25 years recently taking over the business after the owners and founders decided to (finally) retire late last year. He's made well over 12,000 bows and is still going strong (he's only 41 years old--started at CM when he was 17).
Others great longbow bowyers I know of are Ric Anderson, Roy Hall, Mike Treadaway, and Ron Fox. I've never heard anything but positive remarks about them, their work, and their customer service.
None of these guys rely on gimmicks to stay in business, and some of them don't advertise at all. Word of mouth keeps them backed up on orders, and that's advertsing that money just can't buy.
Chad