After Effects related sites dealing with motion graphics, so here's a quick overview of who and what they are.
'Motion Graphics X change' is a great repository of various scripts, presets, expressions and tutorials from its members. You use the search function to finds things and may end up spending quite a bit of time just trawling around. Once you understand they way the siteworks it's a very interesting place to be.
'Batch Frame' is the work of visual effects/motion graphics artist Jesse Toul, and contains a wealth of tutorials, scripts, projects, templates and footage (for sale). he has developed an online tool called Pseudo Effects Creator, it allows you to create tidy little effects controls for your own effect presets, and he also attempts to teach some remedial code writing for beginners.
'Chris Zwar', also the work of one man is like-wise a collection of tutorials, case studies and downloadable projects. He has a long article on Keying and a lot of interesting and useful discussions about various things in and around After Effects. Check out his 'Pre-compose to layer duration' script.
'Quba HQ' is also a designer based site by Quba Michalski who works at Auto fuss in the States. It has a more magazine style aesthetic and encourages browsing and trawling. lots of stuff to discover, tutorials and presets. Go at it.
'Motionworks' is the work of John Dickinson and is sort of like Sydney's version of Greyscalegorilla. There's so much on this site that I'm dis-inclined to attempt writing about it all, I intend visiting it often since I learnt stuff there on my first visit.
'AE Enhancers' is a community based forum for expression and script writers. They often improve upon scripts amongst themselves and so it's a great place to go to see if there are any better versions of your favorites in existence.
A visit to any of these sites is likely to lead to the discovery of other web resources as well, and it's always a good thing to learn new things from professionals about After Effects.