What is the maximum email attachment size?
The maximum attachment size is currently 10MB.
What are the name servers to use for theclientarea.info DNS?
Please see http://www.sonassi.com/knowledge-base/sonassi-name-server-access/
How can I create a subdomain?
Simply create a new folder in the relevant directory.
/domains/example.com/subdomains/mynewsubdomain