It seems like everyone has their say about how to beat writer's block. So of course, I'm going to post a bunch of opinions! (It's what I do.) There's a lot of overlap, but I wanted to post them all so you can see what works for a lot of people. (I'd try those first.)
Personally, if I'm a little blocked, I take a pen and paper and write whatever comes to mind. It's like my Muse is holding the good stuff hostage until I put down what she needs to vent. Or something.
10 Ways to Beat Writer's Block by Tina Morgan has some questions to ask yourself to help you figure out if you're really blocked or if you're just in a little slump. (I didn't even know there was a difference!) Then she gets into some ways to break through that block. I especially like that she says I should take a nap.
James from Men with Pens has some tips. (This post is short and sweet.)
Barry Lyga has some advice about writer's block: Don't Worry About It! (I love this guy's voice and sense of humor. It's worth a read, even if you aren't blocked.)
Write On…with Steve Gottry! gives 17 Sure-Fire Solutions to Writer's Block. He has a few I've never heard of, like listening to music or radio hosts that you don't normally listen to/like. Who knew?
Stick-with-it-ability on Genreality takes unblocking from a structural point of view. Good stuff, as always.
Amy and the Pen talks about what to do if you just don't know how to write something. She says: Write What You Know.