The Potrero View has a post on Christopher’s Book in the Potrero Hill neighborhood in San Francisco. The article gives a history of the book store in honor of its 25th anniversary. Near the end of the article they post the following about the store appearing in Sweet November and also mention Keanu’s patronage.
Christopher’s Books has been featured in a few movies. The most prominent was Sweet November (2001), a romantic drama starring Keanu Reeves and Charlize Theron. “The movie was only filmed outside the store,” Minot said. “The film used a good portion of 18th Street. They turned Christopher’s into a used bookstore, filming a few scenes in front of it. Charlize Theron’s character lived upstairs from the bookstore. She never came inside during filming. Keanu Reeves would come in every time he had a break. He spent tons of money and bought really interesting books,” said Minot.
Bolding is mine.