This is a starting point for GIS books and journals that the UC San Diego Library has, both print and electronic.
If you are looking specifically for materials related to GIS and Librarianship, explore the Map, GIS and Metadata/Cataloging Librarian Core Competencies created and published by the American Library Association's Maps and Geospatial Information Round Table (MAGIRT).
If you are looking for resources on the web, try the Publications & Blogs page in this guide.
There are several GIS publications. Some are completely free and some are subscriptions. When the items are subscriptions and UCSD has paid for or has access to them, the hyperlink will go directly into the UC San Diego Libraries catalog.