Most hosting providers do not support FileMaker Pro. You would need a FileMaker Pro specific host, such as ourselves:
We offer FileMaker hosting, starting at 2 databases (as well as web and email hosting) for $29/month. Mention this post in the Comments blank of your sign-up form to get your first month free as well.
Feel free to let me know if you have any questions about our services either here or off-list to jmay(at)pointinspace.com. Thanks!
- John May