Also, This from Hostgator:
FTP Settings and Connection
This FTP information is found in the second welcome email we send*.
FTP Host/Address: (your ip address)
FTP User: (cPanel user name)
FTP Password: (cPanel password)
If you have not received the second welcome email, please be sure you have paid your initial invoice.
Be sure to upload all files and folders inside the public_html directory.
Place your CGI scripts into the cgi-bin directory.
Upload files and directories that should be accessible through HTTP protocol to the httpdocs directory, and files that should be transferred securely over SSL protocol belong in the httpsdocs directory.
There is also a Hostgator screen cast about FTP details in DreamWeaver, which gives alternative types of 'FTP Host' and 'Username' formats for different types of account.
It might be well worth looking for that 'second welcome email*' mentioned above!