General pages:

• Rio Grande Games - see all Dominion products at the publisher's site.
• Boardgamegeek is the #1 site for all tabletop games, featuring all the information you could ever need, plus discussion forums and much more. This page is for the (1st Edition) base set, click the "expansions" tab to see more.
• Wikipedia has a nice introduction to the game.
• Dominion strategy is the main home of Dominion discussion on the web - the forum and wiki are especially recommended.

Where to buy (UK):

A selection of a few of the author's preferred sites for buying board/card games in the UK - of course others are available!

• Amazon.co.uk
• Boardgameguru (search for "Dominion")
• Gameslore
• Spirit Games

Kingdom Pickers:

These are sites which allow you to randomly choose which cards to use for your next game, without having to physically shuffle cards:

• In Progress has a massively detailed kingdom picker with more options than you are ever likely to use!
• Zack Hiwiller's site is simple and easy to use. But it is missing Empires and the most recent promo cards, and Events are not shown.
• This one has a rather unintuitive interface, but includes all sets, decides whether to use Shelters or Colony/Platinum, and even tells you what additional materials are required for the given set of cards.

Play:

• Dominion Online is the current officially licensed online implementation of Dominion. You can play against humans or bots, with the base set cards available for free, and other sets after payment. Full details of the history of the various online versions can be found here.