Protégé: http://protege.stanford.edu
iSOCO: http://www.isoco.com (local conference organizer)

Previous Conferences:
7th International Protégé Conference (slides)
6th International Protégé Workshop (slides)
5th International Protégé Workshop (slides)
4th International Protégé Workshop (post-workshop information page)

Other Conferences:
10th Conference on Artificial Intelligence in Medicine (AIME 05), July 24-27, Aberdeen, Scotland