The simpliest way is
slocate mysql | grep '/etc/'
It should find the init script, then you will run it with parameter restart.
If it will fail, try
it could find something like /usr/sbin/mysqld so type
/usr/sbin/mysqld > /dev/null &
and the mysql daemon will start.
Another way is to try
slocate mysql | less
this will find every mysql files and you will see where is the init script.