Below are links to some other great CT web sites including CT manufacturers.

MultiDetector CT
CT is us
GE Healthcare
ImPACT
Multislice-CT
MDCT.net (is a continually updated reference website offering scientific information to all professionals involved in or interested in multidetector computed tomography technology and practice. The website aims at keeping the radiology community updated on recent developments, at providing information that may improve standards of practice, and at promoting the worldwide dissemination of relevant guidelines and scanning protocols.)
Philips Medical Systems
Siemens Medical Solutions
Toshiba Medical Systems