Laguna is a census-designated place in the city of Elk Grove, Sacramento County, California, United States. The population was 34,309, at the 2000 census.however, much of the territory incorporated into the city of Elk Grove when Elk Grove incorporated on July 1, 2000. Today it serves as a city neighborhood or district, and home to both the city Police Department and City Hall. Laguna apartments for rent comparison page shows most up to date rent information on Laguna apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.