The Census Bureau collects a wide variety of socio-economic data on United States, Puerto Rico and the Island Areas. For P2 TAPs, the County Business Patterns Database contains a wealth of information about specific industrial sectors including number of establishments, number of employees, and total payroll. These data provide more complete information about the size and economic impact of specific manufacturing sectors which are not readily apparent from looking at environmental data like TRI.
The Census Bureau has a wealth of demographic information available. Below are some useful tools.