Note: The IRC Channel (along with all of Freenode) got nuked.
While the Arduino Project Team provides their official Arduino forums, sometimes real-time help is just a bit better. When that is the case, I encourage you to visit the freenode.net IRC channel, #arduino. While as of today it is not an official channel, there are a number of great people available to help.
You can find me under the nick “baldengineer”, big surprise, I know. Others like kline, Yoston and pwillard are also excellent people to ping with questions.