Quartz Composer wizard Jean Poole (Skynoise) has put together a page to help non programmers and people who come from a more traditional editing background get started with Quartz Composer.
The page goes over some of the most commonly used techniques in After Effects and explains how these can be achieved in Quartz.
“There’s a lot of wonderful possibilities for real-time visual compositing with Quartz Composer. Most existing QC learning resources though, tend to emphasise the generative graphics capabilities of QC. For those with a post-production, animation, motion graphics or VJ background – QC’s composition potential can be difficult to unleash.”
I have contributed some example patches that help explain some of the commonly used concepts in Quartz.
http://www.skynoise.net/quartz-composer/compositing-and-quartz-composer/