I used a spamtrap domain for about 5 years, then the same thing happened 2 years ago. I have not yet had my entire domain blacklisted. I did have to get rid of the wildcard that allows any local-part though. If your MTAs bounce after receipt for invalid local-part, instead of at SMTP time, you're more likely to hit a blacklisting spamtrap address (see spamcop) than if you just happen to be getting spoofed.
I went through my procmail logs with some awk/grep/sort -c and found most of the legit addresses I had used over the years. This took a few hours, as you might expect. Then I changed my virtual file to allow only those addresses and dropped the wildcard. Now all new addresses I give out have to be added before I sign up, etc. I missed a few, but since anything important had high counts (e.g. netflix@example.com) I caught all the ones that really mattered. The spam/bounce volume has been reduced by 99%. The amount of crap w/ wildcard made the inbox totally unusable anyway. It's worth the time. I did have one company I missed go out of their way to call me and get a new address when it started bouncing. :)
With good spam filtering, I now give out my main email address to many signups whom I trust. My main is kevin@somewhere.com, which obviously gets a lot of guesswork thrown at it anyway, so it's not like it will get much worse. It's interesting to note that over the years, I only had two entities leak my address to spammers, and they were caught, larted and the address blacklisted. Not really worth the pain.
BTW, never give your address to tickemaster. They will never stop. I had to threaten their legal department to make them quit.
