It took a little work and some research, but Sentinel SF is back. After its demise in late September, I got a lead from one of our published authors as to a good web host. I got a new (and more logical) domain name registered and a web page up just before Thanksgiving, and this weekend I got it to where I feel it can be deemed officially launched.
The new url is www.sentinelsf.com. Go check it out.