Yet Another Mail Question

["Dennis Soper" <dsoper efn org>]

Hi,

I'm having a problem getting my mail configured and I can't find (or 
more likely, being a somewhat clueless Linux newbie, can't 
understand) the available documentation.

I have sendmail up and running, and want to use it to send mail (some 
coincidence) to my ISP.  Currently, it sends mail when I'm logged on, 
but if I compose offline, the mail never gets sent out of the queue.  
Also, when I send my mail, the return address is 
dennis skye localdomain instead of what I want, which is 
dsoper efn org, as I don't have a domain.  

Is this something to do with aliasing?  Could someone either point 
me to some documentation on how to change this, or explain it to me?

Thanks in advance,
Dennis Soper
dsoper efn org