Depending on your discipline, it may be just as important to record how many times your books and book chapters have been cited as it is to track citations to your journal articles. There are a number of resources that count citations to books and book chapters.
Citation analysis is a quantifiable measure of academic output. Users need to be aware of the limitations and incongruities of citation metrics. Library subscription databases and Google Scholar do not correct errors in citing papers. This means that one paper may be cited many different ways and appear as separate entries in these tools. Also, author and institutional naming inconsistencies complicate these analyses. Comparisons between these tools should be avoided. The databases use different sources to generate data and some are more comprehensive than others.
Book reviews in academic publications not only discuss quality, but place the book and its author in relationship to their discipline. Many academic journals have book review columns. Some disciplines have publications devoted to book reviews.
Library holdings (content in a library's collection) are another metric to include. Librarians curate or purchase materials to support curriculum, research, or general interest. This indicates a degree of visibility and influence that your work has. Remember, researchers sort through a myriad of materials as their ideas develop. Access to scholarship (including books) has value for scholarly impact in a way that is not always quantifiable.