British Film Institute
Huge site containing a wealth of information on film in the UK, a superb reference point for any UK film-maker.

Britfilms.com
All round useful resource for UK producers.

CastNet
Unusually proactive online casting resource who even offer human contact.

Eco Footage
Stock site offering royalty free green relevant footage.

DUMPS
Essential guide on Directing Unsuccessful Motion Picture Shorts from the Filmmaker.com site.

Ebay
Everything from brand new cameras to "second hand" software, the low budget filmmaker's best friend, of course it's ebay.com for the US.

Exposure
Great introductory filmmaking site full of resources and the superb Eejits Guide to Film making.

Kemps
Superb industry directory, completely free to use, 35,000 companies listed in 65 countries.

Mandy's
Superb international production directory with nearly 200 categories.

Mark Litwak
Great resource covering the basics of media law focused on the independent filmmaker.

Met Office
Because if you're shooting outside, knowing the weather outlook is essential. For the US check US National Weather Service

Micro Filmmaker
Excellent monthly webzine full of practical articles and indie film reviews.

Myspace Film
The film section of the free community, upload films, meet lots of people like us; myspace.com/coffeefilms

No Budget SFX
Excellent site on low budget effects and low budget filmmaking generally.

plugincinema
Great site focusing on streaming and web films full of articles and interviews.

Shooting People
Legendary UK resource working around several well subscribed daily e-mail bulletins; free to read, £30 a year to post.

Sonnyboo
The most generous production company on the Net, lots to watch, lots to learn.

Ten Things You Should Know...
Well written common sense essay that every aspiring director should take the time to read, there is also a link to an essay on producing.

Talent Circle
Popular UK community for filmmakers; jobs, casting etc.