This guide by Marcus P. Zillman is a selected list of free and fee based (some require subscriptions), people finding resources, from a range of providers. A significant number of free sources on this subject matter are sourced from public records obtained by a group of companies who initially offer free information to establish your interest, from which point a more extensive report requires a fee to obtain. It is important to note that can be many errors in these data, including the inability to correctly de-duplicated individuals with the same common names. Also note that each service targets a different mix of identifying data such as: name, address, date of birth, phone numbers, email addresses, relatives, education, employment, criminal records. social media accounts, income. As we conduct research throughout the day it is useful to employ both impromptu and planned searches about individuals that are referenced.