If you keep your eye out, you will find beautiful artwork all over the city. From murals on the walls of buildings to the painted electrical boxes around town- there is wonderful art to be seen if you know where to look! I love driving or walking around the city in a new area and being surprised by artwork on the side of a building.
This mural can be found in the North Park neighborhood near Burlingame.
Chicano Park is one place to view murals- http://www.chicanoparksandiego.com/murals/
Murals in Ocean Beach- http://www.oceanbeachsandiego.com/photos-ob-community-murals
Here's a list of various murals you can find around the city- http://murallocator.org/tag/san-diego/
Murals of La Jolla- http://www.muralsoflajolla.com/
Believe me, there's plenty more!