John, just keep track of hosting providers that have to offer, more than just standard shared packages (Like VPS, Hybrids, Dedicated) usually when you upgrade with them, they not only will offer you some discount but as well will transfer the site for you to upgraded servers and you wont even feel the shift other than faster performance of your website.
Its always good to plan ahead a little. People saying Moodle is not for shared hosting, I deny that as I have personally experienced shared host on Moodle and it ran perfectly, spending a hefty amount of getting a dedicated server just to start moodle where you aren't even sure how much time it would take to gather users that will break even the server investments doesn't makes sense to most of the individuals who are privately setting up moodle sites.
but again, a bit of caution, though many shared hosting companies does offer Moodle installation, not everyone will be able to handle that. Once you open your site(s) to public you'll start getting idea of server performance.