Training sites for ISP assitant admin

Hi,

I am currently the Lead-Tech/Assistant Admin for small mainly dial-up ISP.

Does anyone know of some good websites or books for that matter on learning more admin duties. Mostly dealing with mail issues.

Any assistance owuld be appreaciated.

Thanks,
Brian Wright
wrigthweb@wright-onthe-web.com
http://www.wright-onthe-web.com