email id through command line

What do you mean by 'email id'?

Do you mean a user account? check out: man dscl

If you want to use a command line email client, there is the (built-in to OS X) mail aka. mailx client. There is also the option of downloading and installing the mutt client.

See http://en.wikipedia.org/wiki/Mailx

See http://www.mutt.org

". . . is there any way to make new user account for my client through command line???"

Camelot has already given you the answer - dscl. Launch Terminal and type man dscl for usage and examples.