Heinlein is a great writer. Note my final sig line? I'm a bit of a fan. Some of his better books:
Starship Troopers. The movie was...godawful. I was wondering how Hollywood was gonna make an extremely right-wing, political book into a movie. Oh...make it a farce, and a bad one at that. Okie-dokie. The book is wonderful. "...to the everlasting glory of the infantry..."
Stranger in a Strange Land. One of the classics.
The Moon is a Harsh Mistress. Ditto.
Those three can keep you busy for a while.
Mike