A lot of people love this stuff, me included, so I thought I’d put a bunch of them in one place. I keep a few in my sidebar, but not everyone knows about them.
Ladbrokes: That link takes you to tournament winner odds. Be sure to click the various “markets” tabs at the top. There are tons of other interesting bets, such as head-to-head matchups, will-he-make-the-cut bets, and Top American (or French, or Asian, or Senior, you name it). I haven’t explored it all yet, but I just found something called Dual Forecast, which appears to be the equivalent of an exacta in horse-racing. Makes me want to move to the U.K.
OddsChecker: I keep this one in my sidebar. It shows a survey of 24 betting sites and the odds they are currently offering.
Bovada head-to-head matchups: Other places (Ladbrokes, listed above, for example) have these, too, but Bovada has a wider variety at the time of this writing.
BetFair: This is a market. I keep this one in my sidebar as well. This website is most useful a few weeks or months or a year in advance of an event, because the early odds at the bookmakers are usually way lower than they’ll actually go off at. (They do that to protect themselves.) Since this is a market, you get truer odds. (This close to the British Open, bookmakers are showing their hands, i.e., you are seeing their true odds, so this site is less important.)