They do have Wifi but it is a sucure system and it up to whoever you are renting from as to if they want to give you the password or not. My brother stayed there a couple weeks ago and the owner did not give him access.
Don't know about any of the places out that way....but Max's Cafe off Calle 13 has free wifi....and you can even use a computer inside. Black Dog also has a computer you can use to access email. Many of the places in town that had free wifi (or unprotected access) have locked it down.