I thought I had found my own blue jacaranda heaven on Palm Dr. in Beverly Hills. I stumbled down this street on a run one day and was rejuvenated by the abundant blossoming trees; then returned to shoot upwards of 50 snapshots with my camera. Then I found that I wasn't the only one enjoying the "jacs" here (see: this LA Times article on the best places to find jacardandas in LA)
Update: I took these pics a few weeks ago, and unfortunately the trees are already losing their blooms. Be sure to check them out in May of 2009, though. You can still find the beauties in bloom on the Pacific coast of Mexico, however!