As others mentioned, report it to Trulia (thankfully, I've not had a scammed listing on Trulia - thank you Trulia) if appropriate.
I have also 'outed' scammers before on CL by posting follow up ads informing all that the property is leased/sold and to be wary of other postings. It is frustrating and sad that there is very little we can do to stop the scam listings or catch the scammer.
I'm sorry you have experienced this, best of luck!
Please email us firstname.lastname@example.org
Thank you so much, let me know if I can help with anything else,
Ali, Community Manager
If this is a spammer via Trulia you are talking about? I would contact Trulia directly as none of us who are on here answering questions really can do anything. We are individual agents and consumers ion the Trulia site, engaging in dialogue, questions and answers etc. about real estate.
Definately let Trulia know if this is the issue.. but if it is something unethical/illegal regarding a real estate listing, please contact the DRE.