This site has precompiled MySQL binaries for Mac OS X:
http://www.entropy.ch/software/macosx/mysql/
It also has easy to follow installation instructions. You need to use
your Users utility to add the MySQL user instead of the useradd and
groupadd commands. Complete instructions are at the site
I haven't run mysql personally on my OS X box yet but I do know of some
who have and there seems to be a current problem with getting mysql to
quit properly. I think that will be fixed with Mac OS X 10.1 which is
coming out sometime this month. Other than that go to
www.versiontracker.com and