One of the best things about teaching in the 21st Century is the way that technology allows us to be a part of a larger community through newsgroups and listservs. I have gotten so many good ideas and useful tips from the ed listservs that I belong to. That's not to say that my inbox isn't cluttered, it certainly is, but the nuggets that I get are worth the clutter. One of my favorites is Middle-L, a listserve for middle school teachers.
Another one of my favorites is a huge listserv that educators from all over the world subscribe to is WWWEDU. On this list, you'll find educators at all levels discussing everything from technology in the classroom to curriculum development and classroom management. "We Do" is so big that it has its own sessions at NECC!
Another great place for teaching ideas is the Education World weekly newsletter. ED World's website is crammed with teaching ideas, how-tos, and information, and not all of it is tech-related. I also subscribe to Blue Web'n a site sponsored by AT&T, chock full of well-designed lesson plans. They grade the websites they find and will only send out the ones that are of the highest calibre.
For everything from using a document camera to getting stains out of my clothes, I turn to Kathy Schrock. She's the Ed Tech goddess. She's been a teacher for a gazillion years, and has been an ed tech leader for just about that long. You can subscribe to her "Sites of the School Day" news letter and almost every day receive a quick tip or a link to a high-quality website.
There are loads and loads of ed sites out there--join at least one and become part of the worldwide education community!