Falko and Till feedbacks/comments are the only reason I like ISPconfig so much. I used it (ispconfig2-before and ispconfig 3-now) till this day for my websites and hosting needs. Anyways, there are so much information on this forum that you are bound to find a solution or a guide to the right direction on finding it.
I was using ISPconfig 2 for over a year and really liked it, but was lacking on things I really need. It's still a great system and I feel it leaned more toward domain hosters and resellers. I didn't have any use for that since I was the only admin for all my domains.
When ISPconfig 3 came along, I switched in a heartbeat. It had virtual email user capabilities (my favorite feature), replication, more database driven and less of the reseller stuff (forms). Monitoring emails and system from the UI is great! I use Fedora 10 myself and the guide by Falko was on the dot.