Depending of the type of wedding , they might ask you some paperworks. for example in dominican republic , if you are having a catholic wedding , they will ask you to take a six month couple course with your local bpriest and bring the complition letter. you will have to bring , birht certificate, baptism certification , first communion , confirmation paers and if you got a civil wedding before going down there , they will need that marriage license too. you will need to bring the copy of the passport of two of your main withnesses for the wedding ceremony and thats about it.
in cancun, jamaica or any caribbean countries they will ask you the same thing.