Brad,
I in no way represent Spamhaus, but as someone who has had lots of
experience with them, I can assure you that you are not blackholed.
You resolved the complaint how? Did you respond to the SBL? Did you get
an auto-acknowledgement when you did respond to the SBL?
Post up your SBL links here. Let's see what they have to say in them.
You will have a hard time trying to connect with them in any other way
aside for responding via email to the complaint.
I'm fairly sure there are some Spamhaus people on the list, but nanog is not sbl-removals@spamhaus.org. If you're having problems with SBL listings, you need to contact Spamhaus via the link provided on the page(s) for your listing(s), preserving the subject so that your message gets routed appropriately.
IME, if you're having trouble getting SBLs removed, you either haven't contacted Spamhaus properly or haven't convinced them that you've dealt appropriately with the issue.