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.