Here is an excerpt from the FamilySearch Blog:
Earlier this year, FamilySearch announced a free lookup service for genealogy books and microfilm available at the renowned Family History Library in Salt Lake City. The response was overwhelming, 1000s of people contacted us to take advantage of this free service. Another way to utilize this service is to start with limited preview Google Books and get us to scan the entire page and email it to you for free.
The link below takes you the the Blog for an in-depth explanation of how to use the service and how to use Google Books in conjunction with it.
Use Google Books to Get Free Copies of Pages of Family History Library Books