Hi Lineardiver!
Monterey and Carmel have some amazing shore diving sites if you're used to the cold water. I'd recommend starting with the Breakwater at San Carlos Beach. This is a shallow and protected spot with an easy entry as well as plenty of parking and nearby facilities. You'll find a nice dive along the breakwater wall, where you'll see kelp forests, rockfish, nudibranchs, anemones, and occasional sea lions. You can also head to the middle of the cove to swim amongst the kelp, where you'll encounter all of the above and sometimes a curious harbor seal. This is commonly where open water students learn to dive, but it's a fun site for any anyone! Here's some good info on the site:
San Carlos Beach - Spanglers' Scuba.
Another don't miss is Point Lobos State Park in Carmel. I'd probably suggest doing this second after you've had a chance to do a site like Breakwater. This site ranges in ability level from relative beginner to very advanced, but on a calm day, I would not hesitate to recommend it. A guide would be a good idea to get the most out of your experience, as navigation can be a challenge. You'll find a great map of the area at
http://pointlobos.org/sites/default/files/u924/Printable Dive Map.pdf with some descriptions of dive sites. Two good spots to visit here are the Middle Reef or Hole in the Wall, both of which feature amazing walls covered with life and a healthy fish population swimming amidst the kelp. On weekends you need a reservation to dive here, but on a weekday you should be able to drop in. They do charge an extra fee for diving and ask to see a certification card at the entry gate. More information can be found here:
Fantastic Diving | Point Lobos Foundation.
The only problem with California is that our ocean conditions can be spotty and often pretty rough. If the diving isn't great, there's always the Monterey Bay Aquarium, which is one of the best in the world!
