Here is how to set up MobileMe Account on the iPhone:
* iTunes 8.2 or later
* iPhone or iPod touch with OS 3.0 or later
* MobileMe account
Apple iPhone Howto Guide:
1.Type on the home screen on "Settings".
2.Type in "mail, contacts, calendar". Make sure that is selected under "data matching" the option "forward immediately."
3.Just type in "account" and choose "MobileMe".
4.Enter your MobileMe account information, and type in the "Save".
5.Mark e.g. Mail, Contacts, Calendar and/or "Bookmarks".