Congrats on the progress! I'm in the midwest so I can't give you any advice on which ones to go for, but just wanted to mention a few problems I ran into when I switched to open water.  The biggest problems were visibility and over crowding. Open water is kind of a misleading term.  Its often really murky and full of disoriented people who all to easy try to swim right over the top of you.  Oh the joys of open water!

The transition to open water swimming can be a difficult one.  I started racing in sprints last year, where most of the swims were in the pool. I then did a couple sprints with open water, a 600 yd swim at Lake Arrowhead, then a 500 m swim in Mission Bay.  As you stated, it is easier to start to the side or back of the pack.  There is a mass hysteria towards the center and front.  I completed my first Olympic tri this year at Lake Perris.  It is quite a different experience, the first 300 m is packed and you have to be prepared for people swimming into you.  As this is only my second year, I thought the transition from sprint open water tri's to olympic open water helped my comfort level.  Hope this helps.

Tri-California Events puts on the "Scott Tinley's adventures" in your neck of the woods - http://www.tricalifornia.com/index.cfm/Tinley2008-main.htm.  They have an open water sprint distance.  I did the Wildflower as my first Olympic and it was a great scene, but the San Jose International is smaller and you'll have less of a crowd to deal with.

There is a little more fatigue and strain, at least for me it seemed like it. There is a training/seminar this Sat., 8/9, I believe at 9 am at Lake Arrowhead village. I don't know if the tri is sold out, but it might be worth to check it out. The course is hilly, especially the bike. It is stated that there is a 900 ft change in elevation. There is one hill that is steep, and three others that are a steady incline. The one place to watch is a downhill. Hope this helps.

P.S.  The race is Sat 8/16.  If you go up for the training/seminar, be sure to take your bike because they will take you on the course.  Also, last year, we had a chance to jump in the lake at the resort.  Good luck if you do.