Here are some links to good AS3-resources.

Tutorials:

• www.gotoandlearn.com
• www.flashandmath.com
• http://www.senocular.com/flash/tutorials.php

Papervision

• http://dev.papervision3d.org/
• http://blog.papervision3d.org/category/demos/
• http://dailypv3d.wordpress.com/

Libraries

• TweenMax
• CASA Lib – a flexible ActionScript library

Other

• The Flash Blog (Lee Brimelow)
• Mike Chambers Blog
• Preloaders in AS3

Please feel free to submit more as3-resources in the comments field!