What is the best route to take actions against a spamming domain?

A particular site has been spamming all over a local BBS. I am getting really sick of it, and I want to take actions against the domain.

Please correct me if I'm wrong, but IMHO, it's probably the most effective way to counter spam (to nullify the "work" that has been done for the name).

Has anyone done something similar? What course of action did you take? What can be done other than contacting the registrar (I have this feeling that they're going to ignore me)?

Thanks for reading.

p.s. I wasn't too sure where to put this thread, please move it for me if this is not the right place. Sorry.

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