get boxofads trial subscription (1 dollar) and see which yours landing page is getting scraped by BOA, then go inside your Unix server
Open your unix server log files, scan them minutely, closely look for IP's which are of colocating companies in USA, you can do RDNS on a IP and test whether they belong to colo hosting company or not
once you spend time with this, you could locate their IP's - its tedious work which need server admin skills