If you are an investigator and require information on old, deleted or expired Craigslist ads, do not look any further than Harmari Search, which contains a large repository of live and historic Craigslist ads. Note that access to this search is only available to law enforcement, government regulators of industry, professional licensing boards, insurance fraud investigators, and licensed private investigators. It is not available to the public at large. Harmari Search for Craigslist currently supports all “For Sale”, and “Services” categories of craigslist ads in the USA and Canada. Not only does it let you search by keywords, it supports multi-state/city, phone number, VIN or Make/Model/Year searches as well, which is not supported by a traditional Craigslist search.
However, it will only be able to search publicly available content of the ad. For the “hidden” email account used to post the ad, the IP address, unfortunately a subpoena or a search warrant to Craigslist is the only other course of action available to investigators. Visit their legal section on the craigslist website for more information.