what exactly are the issues that it prompts...what is it not accepting?
have you used an FTP program prior to publishing with iWeb?
It shouldnt be too different; check this video tutorial out:
http://www.apple.com/ilife/tutorials/#iweb-ftp
basically with the way to publish it i have found is that:
Site Name: that will end being your folder name
(for example your domain lets say is miles01110.com and you name your site iWebSite it will be
www.miles01110.com/iWebSite) unless you make changes to server address or url, etc in the publisher
Server Address - it could be
www.yourdomain.com, yourdomain.com (without the www) or ftp.yourdomain.com
Directory/Path: where do you want your website published to. leaving it blank on some servers should just put in the top level of your domain, but if iWeb gives you an error you might have to put a / (forward slash) or it could be /www/
as that represents yourdomain.com (the highest level of your site)
say you want to publish it to a new or different folder on your domain you can do /www/myusername/
(so when you publish it will represent as
www.yourdomain.com/myusername/iWebSite)
I recently just got into iWeb myself for publishing some blog/sites and that was the sort of way i discovered how it maps out and how to publish it to my share server.
hope that helps you somewhat.