Skiing Forums (were Jon's username is Spyderjon)
http://www.snowheads.com  
http://www.tetongravity.com 
http://www.epicski.com 

Skiing Instruction in the UK:
http://www.insideoutskiing.com
Run by my buddies Scott & Rob based out of the new Hemel snow centre they offer superb quality & tailored tuition either in the UK or in the Alps. Check 'em out.

Skiing Instruction in Europe:
http://www.warrensmith-skiacademy.com
http://www.easiski.com
http://www.skinewgen.com

Skiing Instruction in America:
http://www.skimartinbell.com      
 
Boot Fitting, Alignment & Balancing in Europe:
http://www.foot-works.fr

Boot Fitting, Alignment & Balancing in America:
http://www.snowind.com
http://www.superiorski.com

Boot Fitting, Alignment & Balancing in Canada:
http://www.lous.ca

Campbell Balancer Analysis (for fore/aft positioning of bindings):
http://www.jonsskituning.co.uk/content/view/33/48/
http://www.realskiers.com
http://www.superiorski.com
http://www.lous.ca