Internal Revenue Service (IRS) Post category:Government & Law Federal tax information, including instructions, forms, and federal tax filing details. Tags: Public You Might Also Like Allegheny County Bar Association August 9, 2018 Primary Sources: Introduction to U.S. History – The American Revolution May 22, 2024 Pennsylvania, State’s Official Website August 14, 2018 Allegheny County, Official Website August 9, 2018