The internet is great at providing a way for people with niche hobbies to connect with one another. For role-playing games, there are a ton of ways to meet other gamers online to discuss gaming. Participating in these discussions is a great way to learn about new games and resources, meet new people who share your hobbies, and get new ideas for your games.
Forums, especially the big ones like Wizards Community, ENWorld and RPG.Net, draw a lot of users and are a good place to get more involved in the gaming community. Big forums do have a downside though – they tend to have a fair amount of trolls mixed into the user base without a good way to ignore them. A trick to make the forums more useful is finding out what categories actually interest you and filtering down to just those categories. For example, I like the What’s a DM to Do category on the WotC forums, but avoid some of the other sections because I find them to be full of complaining and negativity that ends up frustrating me rather than adding to my enjoyment of the game.
In addition to the big forums, there are some smaller sites, like RPG Table Talk, that don’t attract nearly as many users but tend to have a friendlier atmosphere.
There are a lot of gamers on twitter including plenty of bloggers and game authors. A good place to start looking is a search for a game’s hash tag (#dnd, #darpg, or #battletech for instance). Many game publishers also have twitter accounts, and I’ve found that following them on twitter is easier than trying to track all of their RSS feeds.
Gamefiend recently set up an IRC server for gaming discussion that has been drawing a pretty good crowd. You can join the discussion in a browser at the At-Will Webchat page, or if you already have an IRC client, the server is 4eatwill.net:6667 and the channel is #4eDnD. (Edit 8/30/2011: The At-Will webchat is no longer up and running, but another #4eDnD chat has been started on irc.otherworlders.org)
There are more gaming blogs than you could find time to read, and as with any topic, they’re a mixed bag of excellent resources and ranting trolls. At first glance, a blog might not seem like much of a community, but comments allow you to discuss the ideas in a post and trackbacks can link blogs together into bigger conversations. Bloggers love comments and most will be more than happy to answer questions on a post or get feedback on their ideas.
There are two big RPG blog networks that aggregate posts from a bunch of member sites: RPG Blog Network and RPG Blog Alliance. The RPGBN is older and has more members, while the RPGBA was just recently created but already has over a hundred sites in its network. I’d encourage you to follow one of these networks (or both) rather than just individual sites because you’ll get exposed to a much broader range of posts and topics.