As others have said, it really depends. I didn't want either of my kids working while in school either, as I wanted them to focus on their studies and get involved with activities. DD, in particular, had to spend a lot of time studying - school was not easy for her. She graduated with Honors, so in my mind, it was worth it.
We paid for their cell phone, and covered their car insurance and maintenence (no car on campus until they moved off campus). But we didn't give them spending money - they worked during the summer and during school breaks to earn their own spending money. They knew how much they earned during that time, so they knew how much they had to spend while at school. When the car went to school, they paid for their own gas. The first time we went to visit, we left them with extra some money ($100) tucked in their hands as we left. After that, we left them with food from shopping trips.
I don't remember how much DS spent, but I think DD started out trying to keep it to $25/week. But some weeks were less, some more. It really does depend on the school your son is at, as well as the friends and activities he chooses. Whether you give him the money or he earns it himself is really a personal choice, but I would recommend setting some kind of limit that requires him to make some decisions about where he wants to spend it - as opposed to having enough to do whatever he wants.
Books were between $400-$900 a semester, but will vary quite a bit by class, semester, and major. It also depends on whether you can find used ones. Some professors require students to buy the most current version of the text - so finding used might be hard. Others don't care if students use older versions. In some cases, students get away with sharing books. They can be very creative when they are paying for their own books.