Some websites that you will find here belong in more than one category. In those cases, I have put each of them in their most representative category.
www.lynda.com - very professional video tutorials for various domains, with classes for beginners to experts
www.videocopilot.net - After Effects advanced video tutorials, plugins and stock footage for post production professionals
www.redgiantsoftware.com - video tutorials for Red Giant Software products, for beginners to experts
www.trapcode.com - official trapcode suite training by Peder Norrby [the developer of Trapcode plugins]
www.creativecow.net - video tutorials for different domains, and articles
www.motionworks.com.au - After Effects and Cinema 4D video tutorials, and tips to get the most out of your software
www.maltaannon.com - very interesting advanced video tutorials for After Effects
www.allbetsareoff.com - After Effects video tutorials from the famous expert Aharon Rabinowitz
www.filmmakeriq.com - 1001 great After Effects tutorials
www.greyscalegorilla.com - advanced After Effects and Cinema 4D video tutorials
www.graymachine.com - some very useful After Effects video tutorials
www.youtube.com - and, of course, the world's most famous video website
www.sxc.hu - free stock photography site with over 350.000 quality stock photos
www.artbeats.com - great video footage website
www.pond5.com - video footage, sound effects and music
www.alunablue.com - video footage, various subjects
www.cgtextures.com - an impressive collection of various textures
www.myphotoshopbrushes.com - a big collection of Photoshop stuff: brushes, custom shapes, patterns etc.
www.brusheezy.com - Photoshop brushes, textures, patterns and more
www.free-brushes.com - brushes, textures and more for Photoshop
www.iconfinder.com - free icons
www.vimeo.com - Trapcode video gallery
www.trapcode-content.com - Trapcode - user gallery
www.1stwebdesigner.com - Very interesting and useful tips for designers, and much more
docs.jquery.com - the official jQuery documentation [examples included]
www.instantshift.com - 40+ good jQuery tutorials
www.noupe.com - essential jQuery plugins
www.speckyboy.com
www.quirksmode.org - great Javascript explanations and solutions
www.templatelite.com - 100 popular jQuery plugins that are good to know
www.smashingmagazine.com - useful jQuery plugins and techniques
www.designm.ag - 25 jQuery plugins for building navigation
www.mezzoblue.com - inspirational website designs
www.bestcssgallery.com
www.cssheroes.com - interesting website designs
www.csselite.com
www.cssdrive.com
www.cssdesignawards.com - CSS design awards
www.designshack.co.uk - great website designs
www.thecssawards.com - a gallery of the most prestigious websites in the world created with CSS
www.cssmania.com
www.themes-css.com - themed CSS websites
www.cssgallery.ro
www.divinecss.com
www.cssgallery.com
www.csscollection.com
www.speckyboy.com - great and inspirational website designs