Well, it took longer to get the site turned back on, but ThreeStooges.net is back up now.
The problem was with a query that apparently was bogging down the database enough late yesterday afternoon to effect other web sites on the same server, so the hosting tech support staff turned the site off and notified me of the issue. After identifying the problem I made some changes to the database (adding indexes to a number of tables to speed up processing) and I changed the scripts to eliminate that query. Tech support approved the changes and notified me that they were going to re-enable the site, but for some reason no one ever actually turned the site back on last night.
Unfortunately my home internet connection crapped out just after receiving the message that they would re-enable the site, and I wasn't able to reconnect until late this morning, and that's when I discovered that the site was still switched off. I was finally able to get tech support to bring the site back up, and hopefully it will stay that way.