Resource Links, Look here for all your needs.

[Slackiller]

http://www.slackiller.com/tutorials/tutorials.htm
http://collective.valve-erc.com/
http://countermap.counter-strike.net/Tutorials/
http://www.slackiller.com/tommy14/tutorials.htm
http://server.counter-strike.net/maps/tutorials.php
http://www.snarkpit.com/tutorials.php
http://cariad.co.za/twhl/tutorialbrowse.php?tuttype=1
http://www.planetquake.com/worldcraft/tutorial/
http://articles.thewavelength.net/
http://www.vlatitude.com/tutorials.php
http://www.planethalflife.com/schrade/theproject/main.htm
http://www.karljones.com/halflife/almanac.asp

need some tools for mapping?
http://collective.valve-erc.com/index.php?go=mhlt
http://www.slackiller.com/hlprograms.htm
http://countermap.counter-strike.net/Nemesis/index.php?p=1