Hi casinotime,
I can recommend you Intercasino Latinamerica. They are already recognized on a few spanish speaking countries so this will make easier for your traffic conversion.
If you are targeting to Spain traffic, then google.es is a good place to start and see what casinos show up. Also, try some spanish keywords such as tragaperras, ganar con casinos, ruleta, etc.
If you are targeting to Latinamerica countries, then you can do some reasearch with google for each of those countries.
Cheers,