[jaredsohn]

Reddit /r/loseit and /r/fitness have excellent FAQs for weight loss and becoming fit and they offer communities if you are looking to learn or for support.

http://www.reddit.com/r/loseit/wiki/faq

http://www.reddit.com/r/Fitness/wiki/faq

[SheepSlapper]

/r/loseit helped me lose about 50 pounds, and getting another desk job helped me gain about 20 of those back :)

Regardless, loseit is highly recommended.

[angersock]

/fit/ on 4chan is an interesting place.