I am not clear about what you seek.
If you're looking for women who are not prostitutes and if you speak good Spanish, you'll have many opportunities outside San Jose for traditional dating.
Cities such as San Isidro del General, Ciudad Quesada and University towns will provide you with a huge number of beautiful non-pro women for meeting, greeting, eating, dating and mating. But these women will require a more traditional dating program, so please do not try to bed them the first night or presume that they are prostitutes. Most are not.
Yes, prostitution is available outside San Jose, and depending on the locale, the women could be very nice or frightening.
If you're talking about finding prostitutes, you are limited to San Jose, a couple locations in Jaco, a couple places in Puntarenas, and independent working girls scattered over the countryside.
Here's a short list of places to find pros.
Puntarenas = The Green Door, plus independents in several bars.
Quepos/Manuel Antonio = Bar Rosa, Itsamana (clip joint, avoid), Wacky Wanda's (bar with a few independents), local restaurants and street dances on weekends.
S. Isidro d. General: Bar Mexicana, usually low quality.
I'm sure other vets would be able to add to this list.
If you could be a little more specific (location, pro vs. non-pro etc.) I might be able to point you toward what you seek.