Studying the subject and art of Impovising/composing

I love the way people improvise songs in rock style, ballad and other things. There are people who can play an entire rock song that contains no piano on a piano solo and the result is amazing! I've officialy decided to start studying different styles and techniques of improvising and music inorder to better myself at arranging songs on the piano. I just spent 20 dollars ordering a book from a music store that is all about Rock 'n roll piano. It says that it contains many techniques for you to play like jerrald louis or someone like that name, I can't remember the names really. I'm going to see if I can take some of the old piano rock masters techniques into my playing. But I'm wondering what else I need to do to learn to improvise/arrange solos on the piano. Any ideas besides practicing other music and my piano lesson homework.