The POP3 and SMTP servers are always mail. and then your domain name. For example:
mail.boyddesign.com.au
mail.domain.com
We recommend for your SMTP server, that you use the one provided by your Internet Service Provider (ISP). Here are some SMTP servers for ISP's:
Bigpond: mail.bigpond.com
iiNet: mail.iinet.net.au
Internode: mail.internode.on.net
iPrimus: smtp.iprimus.com.au
Optusnet: mail.optusnet.com.au
TPG: mail.tpg.com.au