Months ago, I stumbled across Konkuri thanks to the Download Squad. It lets you organize tournaments painlessly with a good range of customization such as round robin or bracket tournaments, the number of rounds per set, and randomly generating matches.
The real beauty of Konkuri is that when you register for a free account, all your tournaments are permanently saved to the database to view for posterity. For example, this past afternoon, I held an amateur tournament for the CSULB Gaming Club. Here are the results to the past games.
Tekken 6 singles, round robin
Brawl 2v2 teams, round robin
Brawl 2v2 ver.2, single elimination
The only feature missing that I wish it had was double elimination. Fortunately, I got a hold of another tournament organizing software, tio. Double elimination is a much more speedy way to get through the matches while still giving everything ample chances to win. Of course, since its software, it's not available for public viewing, but you can save files for easy viewing later. Here's a screencap of the Blazblue singles tournament with double elimination.