The Bet Resources
Go ahead and geek out, big time. This site has links to bios, online texts of his plays and his other stories, and a bunch of critical essays about his work.
Here's the text of the short story itself so you can read it on the go.
Movies or TV
This awesome episode of The Twilight Zone was based on "The Bet." In this case, the bet is that a man won't be able to not speak for an entire year. And the twist? The guy who bets against him can't pay up, but then it turns out that the guy was keeping silent because he'd had his vocal chords severed and now will never be able to speak again.
Articles and Interviews
Remember the good old days when folks wrote letters? Chekhov was no exception, and he was a pretty good epistler, if we may say so.
Here's a British take on the short story—about 15 minutes long, and pretty awesome. Check out Part 1, and then be sure to click on over to Part 2.
If you're too lazy to read this short short aloud to yourself, maybe you could take a listen to these recordings.
The spectacles ain't so bad, either.