There are two different types of FTP accounts used at Hostmonster, or any other hoster that uses CPanel as I understand it.
The first is when you use your FTP software to connect to your account with your main account user information. It would be something like this:
Address: <domain.name> OR <IP Address>
user: <CPanel account username>
password: <should be obvious>
The second type of FTP account would be one you created, or an annonymous account, all of which would use the following information to log into your HM account:
address: <domain.name> OR <IP Address> // if <domain.name> does not work, try ftp.<domain.name> or look for a field where you can enter the port number 21.
user: <accountName>@<domain.name> // notice the striking resemblence to a standard email address. You have to use this entire thing to log into your account with a FTP account OTHER THAN your main user account.
password: <should be obvious> // also anonymous account like ftp and anonymous do not have passwords associate with them. They are also limited in their permissions.
Please note that anything inside these marks " < > " should be interpreted as "enter your domain name or username here". Do not use " < > " when entering your specific information.
~regards