the reason you are having this problem with selection is that you are shopping in almost July.

Chain stores have seasonal stock based on the whole country, not southern California, so swimsuit season is summer, which means you buy a suit in spring, which means stores are mostly on their last dregs of swimwear at this point.

I know for a fact that target has/had boy shorts, and lots of non-skimpy, non-dangly thing suits. They also have vintage-y inspired "swim dresses."
http://www.target.com/Merona-1-pc-Halter-Swimdress-Black/dp/B0017YR998/qid=1214351684/ref=br_1_3/601-5368344-9047356?ie=UTF8&node=13706071&frombrowse=1&rh=&page=1
http://www.target.com/Merona-1-pc-Bandeau-Swimdress-Black/dp/B0017YR98E/qid=1214351733/ref=br_1_9/601-5368344-9047356?ie=UTF8&node=13706071&frombrowse=1&pricerange=&index=tgt-mf-mv&field-browse=13706071&rank=-product%5Fsite%5Flaunch%5Fdate&rh=&page=1