Here are some websites, blogs and specific threads that I enjoy.
http://www.bolterandchainsword.com/ Great forum for marine fans, good tutorials subsections.
http://platoonbritannica.com Some amazing painters in here and a really nice community.
http://warhammer.org.uk/phpBB/ More for gamers really.
http://www.ribblewarriors.co.uk/forum/ Local gaming club I have been to. A nice bunch
http://www.fullrepent.fr/ Amazing works!!!
http://www.jrn-works.dk/ More good stuff and some nice tutorials.
http://spikyratpack.blogspot.co.uk/ <--- awesome!!! Really nice guy too!
http://arsiesweb.com/ <---awesome work and great tutorials!
http://drownedinplastic.blogspot.co.uk/ <----awesome work! Great tutorials too.