And I can completely understand why you would dislike D'Souza.  He copiously documents all of the points in his books, and his facts are indisputable.

But his books are not the only source of information to discredit the Democrat narrative.  Pick up a good history book, like the Oxford History of the United States or some other scholarly general history.   Read the autobiography of Frederick Douglass.   Read a biography of Andrew Jackson.  

Basically, read books instead of relying on TV and movies,  and try and find sources as close to the place and time of the events that occurred.