Although spammers try hard to mask their identities, in some cases you will be able to track them down to report them. This is usually fake, but not always. Even if you suspect the address is phony, it's a good idea to get in touch with the ISP or domain owner to let them know their domain is being used in this fraudulent way. Domain owners have successfully sued spammers abusing their domain names in this way.
Many spammers use a Web site as a point of contact.
It's often possible to get in touch with their Web host and get the Web site shut down. Often this is a fake address or one unrelated to the spammer. However, sometimes this is a real address owned by the spammer. If the number rings through to the advertiser's office or home, this can be a way to speak directly to the person to let him know how you feel about his advertising practices. If it rings to a voicemail box, you can still leave a message expressing your opinion.