We have the same trouble on these forums from time to time. I acted in the same way as you. I barred the trouble makers and was up front about deleting their postings but I did not publicize the fact I had barred them because that only antagonizes the situation and would encourage them to come back again. You'll notice the IP logged message in the corner of each posting that allows me to ban based on IP address. Banning by email address just wasn't enough.
[This message has been edited by Nigel (edited 11-27-2003).]