The LibGDX project enjoys a steadily growing and active community. If you ever find yourself stuck with a problem and you just cannot figure out how to solve it, check out the official forum at http://badlogicgames.com/forum/. There is a great chance someone else has already asked your question and has even found a solution with the help of the community. Otherwise, do not hesitate to ask your question on the forums.
There is also an official IRC channel (#libgdx) on Freenode (https://freenode.net/) where you can find some of the users and developers to talk about LibGDX.
If you want to read about the latest news on development of LibGDX, visit the blog of Mario Zechner who is the founder of the LibGDX project, or follow him on Twitter using the following links:
LibGDX website (http://libgdx.badlogicgames.com/)
Mario Zechner's blog (http://www.badlogicgames.com/) and the Twitter link (http://www.twitter.com/badlogicgames/)
Also, check out the following links for more in-depth information:
API overview (http://libgdx.badlogicgames.com/nightlies/docs/api/)