Cliniweb International:  Hosted by the Oregon Health Sciences University, this is a useful way to search not only the medical literature (such as with MedLine above) but various web sites offered on the internet.

Medical Matrix:  Search specifically for health related internet sites on the WWW.  Lots of health related links and easy to figure out.

>>MedLine PLUS:  This is the National Library of Medicine's web page for patients with an interest in finding their way thru the medical literature.  This site allow patients to search through the same medical literature physicians rely on extensively.  This sight does take some familiarity with medical terminology & can recover some very technical information.  May be a good idea to ask your physician for some "keywords" that might aid in recovering relevant information pertinent to your disease(s) of interest.