1.How2USA and chinese restaurant news Magazine 2.ICANN Domain name register infomation 3.Online update by chineseyellowpage.net and 5zip.com 4.Search engine,directory,business list clawler 5.phone calls to verify information. Every business is called one a year. 6.County Courthouse and Secretary of State Data 7.Leading business magazines and newspapers 8.Annual Reports 9.10Ks and other SEC filings 10.New business registration and incorporations 11.Postal service information including National Change of Address, ZIP+4 carrier route and Delivery Sequence Files 12.Yellow Page and Business White Page Directories