First, thanks J.D. for your gracious reply. The thing is, I set up the auto start feature (or whatever it's called) to start the mysql server along with the computer. But I tried your suggestion anyway, and it told me the port was already in use (i.e. the server had been started).
I had created a symbolic link to /private/tmp yesterday but had not been able to see if that worked just then...apparently it did, because mysql starts right up now.
Incidentally, here is where I found this fix:
http://www.iwalt.com/weblog/2003/01/mysqlsnafu
And check out this comment:
"Hey man. Safari is causing the problems with tmp folder. See macfixit.com. Seems it likes to delete it, and sometimes the home directory? Anyway, just do a little "ln -s /private/tmp /tmp"
Daniel
-Yikes, that sucks.
But thanks again for your response, I appreciate your taking the time.
-Chad