There are a huge number of sites devoted to various aspects of the hobby; here are a few of our favourites.
Stargazers Lounge (SGL)
By far the best astro forum on the interwebs. The regulars on the forum are experienced but also incredible helpful and welcoming of novices. You will get great advice and learn loads if you join this forum. They also have a great buy/sell forum where you can trade good kit with trustworthy people (currently out of action but due to be reinstated soon).
To help find your way around the night sky, Skymaps.com makes available for free each month the Evening Sky Map – a 2-page monthly guide to the night skies of the world – northern and southern hemispheres, and the equatorial regions. Each issue contains a detailed sky map, a monthly sky calendar, and a descriptive list of the best objects to see with binoculars, a telescope, or using just your eyes.
Messier45.com constitutes a non-commercial effort to provide the deep sky observer’s most valuable tools online; the map and the lists of objects.
News and information about the Sun Earth environment.
One Minute Astronomer
The idea behind One-Minute Astronomer is simple: it will help you build your knowledge and appreciation of astronomy, one small step at a time.
Enter your location and get information on satellite passes visible from where you live.
The Astronomical League
The Astronomical League is composed of over two hundred and forty local amateur astronomical societies from all across the United States. These organizations, along with our Members-at-Large, Patrons, and Supporting members form one of the largest amateur astronomical organizations in the world.
Amateur Astronomy Magazine
Based in the USA, Amateur Astronomy Magazine is written by amateurs for amateurs around the world. Covering all aspects of amateur astronomy from telescope making and star party reports, regular deep sky and lunar columns, and imaging articles, an electronic subscription is very competitively priced for subscribers.