Hi these are most cool resources: [url=http://www.warmforestflash.com/blog/2009/01/top-8-resources-for-learning-actionscript-3/] The Essential ActionScript 3.0 by Colin Moock is a very big book which is describing everything about actionscript, but for the begginers i recommend the Learning ActionScript 3.0 by Rich Shupe with Zevan Rosser book, which is better for begginers. Good luck!!
I learned mostly from books like O'reilly learning actionscript and essential actionscript. You don't have to buy them you library should have them. Also it's made by Adobe http://oreilly.com/catalog/9780596527877/?CMP=AFC-ak_book&ATT=Learning+ActionScript+3.0%2c