1.) I use, findthecompany.com, wysk.com, manta.com and other search engines very well to search and locate the list of company or business websites, owner's name and executives, locations, contact numbers and email addresses. (oftentimes these data are available at facebook, twitter, Linkedin.) 2.) I use 'ctrl f' and type the keywords to find quickly the name related to the information. 3.) I also use google search to find accurate email. ("name" email @gm.com filetype:pdf OR filetype:xls OR filetype:doc) This strategy is very effective. I also use whoisdatabase.com as another search engine for email.if the email cannot find in google or websites another effective way is finding emails through rapportive.