by Rick Jerz.
Diane, there are many places to start, and others might be able to direct you to the many resources available on moodle.org, including documentation.
My suggestion is to first find out what versions of mySQL and PHP are on your hostserver. Then, look at the Downloads webpage and make sure to pick a version of Moodle that works with your versions of PHP and mySQL. Until you determine this, it is hard to direct you to the correct version of the moodle docs.