I am unsure if your looking for books on running a lawn maintenance business or looking for books on how to take care of the grass in your lawn.
suggestion on taking care of grass:
Jerrybaker.com
Orthobooks-all about lawns
www.amerinursery.com - both lawncare and business
The Chemical-Free Lawn-by Warren Schultz
Lawn maintenance operations:
www.turfquip.com/nilsson.html
www.vanderkooi.com
Books:
Lawn Aeration-Turn Hard Soil into Cold Cash by: Robin M. Pedrotti
A Guide to Developing a Landscape Maintenance Business
Published by- Associated Landscape Contractors of America and National Landscape Association
These books can get very expensive so read discriptions carefully
before you by:
hope this helps