Sylpheed and Kmail are email clients (like M$ Outlook, Eudora, etc), which allow you to retrieve, read, and compose email. Other features differ from client to client. The primary benefit is that they provide a gui interface which is fairly easy to navigate and provides the user with an environment to which they may already be accustom.
The only bits of information you need to run them are:
- pop/smtp mail server name (i.e. mail.attbi.com if your ISP is at&t)
That should then allow you to retrieve your email from you ISP's mail server. If your email comes to your local server directly (i.e var/spool/mail/username), then you can set the clients up to check that mailbox as well.
I'm currently using Sylpheed on my Slackware 8.0 box and Ximian on my Red Hat 7.3 laptop.
You can check out www.freshmeat.net
for current versions of those clients as well as find others.