IAmstermdam - 'I amsterdam' is the new motto for the Amsterdam Area and this website is the official site of the City of Amsterdam, in connection with many of its partners. A comprehensive and authortitative site, it is a good starting point to find out more about the city, both for tourists as well as residents.
Amsterdam Info - An easy to navigate site which contains tourist information and recommendations for accommodation, hotels, apartments. Also features events, maps and suggested itineries.
Internet Guide to Amsterdam - A text based site, with basic information, written and is designed to be easy to print and carry around with you. Apart from basic information on maps and language and electricity, the site has a good list of eating places, though if you are a tourist, you may be hardpressed to find the time to try them all out.
Lonely Planet - This is your typical lonely planet site. With basic information, and not much more than you would have found in the sites before. The Places to See section has a very long list of any possible attraction you could think of, listed alphabetically - not very helpful if you don't know where to start looking, but if you are looking for more information on something specific, this might just be the site to look for.
Time Out - Time Out guide, as they claim, is your guide to a good time in Amsterdam. Apart from the usual features and listings, Time Out has a good listing of coffee shops and a section for gays and lesbians.
Wikitravel - Community edited website containing basic information and tips about visiting Amsterdam. Also contains information on how to get in to Amsterdam and get around while you are here, as well as a good listing of hotels, by any budget range.
Amsterdam Tourist - The official site of the Amsterdam tourism & convention board, Amsterdam Tourist is definitely a site worth checking out. Especially good is the event listings around town, so you can make your visit just that little extra special.
Amsterdam Hot Spots - Perhaps not the most visually pleasing of all sites, but Amsterdam Hot Spots has a good listing whatever it is that catches your fancy. The categories they cover include eat, drink, lounge, music, smoke, gay, club, red lights and sleep.
Underwater Amsterdam - Hip bi-weekly 'street' guide online, with information on music and other activities and services. Easily browsed layout. Created by an Amsterholic, it has wealth of useful information for the discerning traveller and Amsterdweller.
Smoker's Guide - If you intend to try out the soft drugs that are in offer in Amsterdam, best to know about before you try. A site that is painful on the eye, it nevertheless has much information to ensure you will know what you are tying out, and be safe in your adventures. Recommended read before you go coffee shop-hopping.