Here are some sites that I have found to be of great value:
http://www.chessopenings.com - NM Dereque Kelley explains openings very well.
http://www.thechesswebsite.com - Excellent videos.
http://www.chessvideos.tv/ - An abundant resource of top notch videos.
http://exeterchessclub.org.uk/category/topic/coaching - Excellent articles
http://www.chesscafe.com/column/column.htm (especially Dan Heisman's Novice Nook columns - http://www.chesscafe.com/heisman/Novice_Nook_by_Dan_Heisman.asp and Mark Dvoretsky's Instructor columns - http://www.chesscafe.com/dvoretsky/dvoretsky.htm) - I can't recommend Dan Heisman enough, his videos on ICC (not free) are excellent.
http://www.50chessgames.freeserve.co.uk/ - I stumbled upon this. Looks helpful especially since the games are annotated.
http://www.janmatthies.info/chess/cvt/cvt.htm - Improve your visualization.