The domain that I am using and the only I have for my website is from one.com, I don't know what about others company offer but so far, I can see that I don't have problem at all when using ftp to my website.
Furthermore, they have support 24/7. So, you can shoot any questions anytime you want. Good luck with using iWeb and I have a tip for new bie using iWeb
When you create a website by iWeb, you should always backup your website by come here:
Macintosh HD:User:Library:Application Support:iWeb
Inside iWeb, there is a file name Domain, this is the one contains your website, if you have time machine then I will not mention about that. If you don't, you should always backup this file if you want to continue building your website later incase your mac is crashed.
Here is my experience because I was screwed up when I tried to clean install my MBP. I thought it was ok when I tried to publish my website to local folder, because the whole website would be here and I thought I can put it back to iWeb but I was wrong.
So, I also have another problem with php, apache and I would like to shoot here too. If anyone got the same problem, you might find this way. By default, php and apache is not enabled in Mac OS X 10.5. So you should enable it first to use it. Here is the link that save me after 2 days I was like really mad why my test.php not working on my web sharing
Enabling PHP in Mac OS X 10.5
So, if you want to learn php by yourself, and got same problem . You can try to follow that link to solve the problem. I think there are lots of way to fix it but this guide is clearly to read for non-speaker english like me.
Good luck all
SG