I'm not sure where, but there are tons of free backing tracks and drum loops out there that might just be as simple as downloading opposed to creating your own. Drum patterns tend to be the hardest (from a guitarist's point of mind) to lay down/create.
When I first got a mac (2008) and got into GB, I bought a few wonderful how to books, used off of Amazon pretty cheap. They are similar books with tons of diagrams/illustrations and great specific how to's. They helped me alot. Imagine there are new ones out for the newest edition of GB as well. GB is actually lots more in-depth than people give it credit for. So nice and easy to get up and creating, but there are MANY features the average user isn't even aware of.
Best of luck to you.