Congrats Victor! Some people turn up their noses at venues like that, but not me! Exposure is what it's all about. It's amazing how far simply asking can get you.
You will get a significantly different audience at the library than at a gallery. Basically people who don't necessarily care very much about art, but who can be greatly moved by an image that has some meaning for them. Figure out what connects with your audience, put lots of that in your show. One thing that always sells is very dramatic pictures of locally themed images. Landscapes, landmarks, etc. Think magic hour, you can never go wrong with magic hour shots. For instance I have sold a remarkable number of pictures of city parks...very atractive pictures to be sure, but parks none the less. If there is a dramatic overlook of your town, be sure to include that (at magic hour of course). Don't bother too much with merely pretty pictures, if they don't connect they won't sell. Watch your price point, check some successful local galleries and don't go any higher than what you see there. Not having to pay a commission gives you a huge competitive advantage, figure out what you would have to charge if you were paying a 25% commission, price accordingly.
If you have the right stuff (in your show) you can easily do $7k+. However, to sell that much stuff it is almost imperative that the library process sales for you. That's the big thing, you need to make the sale while the customer is still feeling moved and at the scene. No matter how moved he might be, if he leaves scene without paying you have almost certainly lost the sale. A distant second is that your tags say "To Purchase This Image please call xxx-xxxx." Get yourself to the scene ASAP, or make arrangements to deliver the piece to your buyers home or workplace (always offer the workplace option, some buyers don't like people coming to their houses). In this sense a small commission of even 25% would be to your advantage if somehow that could induce them to take sales.
Also be sure you have some replacements on hand. Don't let empty spaces appear on the wall. It's little things like that make you an attractive invite-back, the guys who run these venues have a lot to do and strongly favor artists whom they perceive as reliable and easy to deal with.
PS your link doesn't work, I get a permission denial.