If you are looking to get traffic from Mirc, you may need to contact the channel OP or Super OP for advertising. However, I'm not sure of the traffic quality from IRC.
About detecting spam traffic, I would ask the domain seller for a 1-2 day nameserver change to my servers for traffic testing. You could set up a quick minisite or blog and either add Google analytics or some other stat monitoring program. That should give you an idea about the origin and legality of traffic.