I love San Clemente, California for its surfing, but its tech scene is probably non-existent, and the COL is high. Oceanside, CA, the northernmost town in SD County, is probably the most affordable surf-proximate town in SoCal - moonlight in Encinitas and Scripps pier are both relatively close, and there are some ok breaks that you can walk to in Carlsbad and Oceanside. As far as tech work, I think you're probably best off finding a specific employer in/near a surf town, rather than trying to find a 'tech hub' to live in and look for work. If you're looking to do freelance/startup work, try looking for incubators in a few towns and then go visit them. Maybe you'll discover a small start-up community.