One thing I think libraries really need to get on is digital preservation. Look at what the Internet Archive has done and think about how important and how expensive it will be in the future. Public libraries collectively have the funding but perhaps not the expertise.
I had this at home in Australia! I could order books from countless libraries. In the Bay Area, my own local library unfortunately doesn't have anything like this but the San Francisco library does. I recall having a book brought in from Sacramento.
I'm served by the Santa Clara County library system and I believe any thing of which they have physical possession (DVD/book/tape/etc) can be transferred between any branch for your convenience. Where exactly are you?
The same reasoning can be applied to most of the things your taxes pay for though. How often do you need to call the police or the fire brigade? I haven't needed either in a decade either.
There are likely other things your taxes pay for that you use more than other people as well. For example my city allocates a huge amount of money towards maintaining roads, which I never use and sidewalks, which I use more than the average resident.
A few things, like police and fire services I think most people are willing to pay for, they can see they may require them. You could make an argument that insurance companies and volunteer fire departments could provide a sufficient level of coverage, but ultimately for police especially you're probably going to pay a fair bit for it.
I think there's good arguments to privatize roadways, or at least some aspects of them. But at least roadways and sidewalks are things that just about everyone uses at some point, even if indirectly.
Libraries on the other hand probably only benefit a relatively small percentage of the population at all and only in a significant way to those who directly use them. They represent a particularly high level of waste in my opinion.
Looking at my own public library, the city spends $5.7m per year for libraries serving 90000 people ($63/pp). That's 2.85% of the city's total revenue, which comes from sales tax, property tax and business license tax.
