While searching for information on a specific type of fracture, I found the beta version of Google Scholar. It is worth a look. From the site, and explanation:
What is Google Scholar?
Google Scholar enables you to search specifically for scholarly literature, including peer-reviewed papers, theses, books, preprints, abstracts and technical reports from all broad areas of research. Use Google Scholar to find articles from a wide variety of academic publishers, professional societies, preprint repositories and universities, as well as scholarly articles available across the web.
It's worth a look.