Is your hosting compatible with Macs and/or iWeb?Using a Mac is not a problem. Web servers are in general platform independent. Our control panel is accessed via the web, so it doesn't matter what computer you use as long as you have a web browser.
If you are using iWeb, you can use it to make a website and then upload it to any web host. You will need to use an FTP program like Fetch to upload the files, rather than using the built-in tools that are synced with MobileMe.