A site that will probably answer most of your questions. However, always be wary of equipment reviews in magazines and associated websites that are funded by advertisements paid for by the equipment manufacturers.
For detailed camera reviews the following are useful sites.
The web's most comprehensive site devoted to the art of landscape, nature and documentary photography using digital as well as traditional image processing techniques. You will find on these pages instructive feature articles, product reviews, travel and technical discussions, inspiring portfolios, and a Discussion Forum.
Cambridge in Colour is an online learning environment where photographers can come to improve their skills.
Pixel-Peeper is a lens and camera comparison site. You can examine full size pictures from a specific lens or camera, (more than 1,000,000 photos are available), also based on a specific setting (e.g. aperture, focal length or ISO). If you'd like to find out more about how to interpret sample images, check out the tutorial. Each lens/camera page also lists a number of online stores and eBay auctions along with availability that you can use to purchase equipment, or simply to check prices.
Best Buy have an excellent lens buying guide including basic lens features, choosing the right lens, types of lenses, accessories and advanced technology.
This link to SoftwareHow gives a comprehensive guide on how to fix memory card errors. On other pages of SoftwareHow, you'll find practical advice that will help solve problems related to your computers and digital devices.
Waylandscape is a site run by and dedicated to the landscape photography of Gary Waidson, a regular speaker on the L&CPU circuit and beyond. Gary features prominently in the Take a View Landscape Photographer of the Year competitions and his site has tips on how to get the best out of your camera.