American Cancer Society: This is a superb site for nearly all types of cancers. A great starting point to begin a search on a particular topic, or just cancer in general.
John Hopkins Pathology Pancreatic Website: This site is perfect for anyone wanting information specifically on Pancreatic cancer. It contains one of the most extensive Pancreatic website databases ever created.
Steve Dunn's Cancer Guide: This is a site created by a survivor of cancer. It provides a lot of other trustworthy sites, and it is meant mostly for people with cancer, but it also provides information for people reasearching cancer, as well.
Cancer Links: This is, as the name aptly states, a site devoted entirely to directing viewers to hundreds of reliable sites about a certain cancer. Very easy to use, and contains sites for most of the major cancers.
Cancer Quest: This is an extremely detailed site about the "biology of cancer". It covers nearly all the information you would need to know about the scientific side of cancer, from what a cell is to the treatment of cancer. Very easy to use, and very helpful for anyone interested about cancer!