There are many ways to identify the availability of a book and whether or not it is in print. The order of this recommendation includes priorities for UCI users. Increasingly, books are becoming available as eBooks. There may be multiple records for the different formats in Library Search.
Finding book chapters is increasingly important and available in the digital arena. Many eBook platforms allow one to search at the chapter or full text level, and those will be noted in each subject area.
There are many eBook resources - reference titles, collections from many publishers (Springer is the largest publisher represented) known for scholarly and professional title releases. These are scholarly societies and commercial publishers. They are identified in Library Search as available via the Internet and many are listed on different Subject Guides.