Hey all!

I hope you can help me, my system administrator has gone MIA for the past few weeks and I really need some guidance

I have a dedicated server using Redhat Linux software.

1] I know how to create pop accounts through telnet, but I don't know how to delete a pop account through telnet

2] Catch-alls. I have about 12 domains on this server and would like to delete about five of the catch-all accounts since they have only accumulated spam and we don't use them.
~ How do I delete a catch all? If I delete a catch all account, can I still have a pop account on that domain?
~ How do I add a catch all?

3] My system administrator has it set up so that my system does mysql database backups each night (my guess through a cron script). How can I find where that script is and make changes?

Any help you can give me would be immensely appreciated!

(Lastly, are there any good newbie linux sites that show how to maintain things like this?)