Just finished reading a very interesting article on Breaking News From Chess Life Online by Elizabeth Vicary (Chess Beach Reading). She writes about the tactics of chess and two new books. Click on over AFTER reading this and you will be glad you did!
I came across a website on tactics the Chess Tactics Server, (http://chess.emrald.net/) but have not had the time to check it out. I did suggest it to Samuel Zimmerman, who came in last night with good things to say about it, and that's good enough for me!
I've heard top players say that chess IS tactics; but, then again, I recall reading where GM Jonathan Rowson said he went from IM to GM after reading Positional Play (Batsford Chess Library) by Mark Dvoretsky and Artur Yusupov. Victor Korchnoi said, "Chess you don't learn ... chess you understand!"
Can it be that one can LEARN to UNDERSTAND chess? If so, may I suggest you read The Art of Learning: An Inner Journey to Optimal Performance by Josh Waitzkin, before you attempt trying to understand the great game of chess!