Of course, these database templates provide basic sample databases, which
provide a "starting point" rather than full-featured applications. There are
many inexpensive, professionally written library software packages
available, often for no more than the cost of a few books. Do a Google
search for "library software" and you will find many hits. Undoubtedly there
are shareware and freeware packages available as well.
Finally, you might be interested in a library system that I have written and
made available as freeware here: