Hi Abbad,
did you already encounter this page on the website of the Department of Antiquities?
The Law of Antiquities (
http://itp-jo.com/daj/En/inside.php?src=sublinks&SlID=5017&MlID=5 ) suggests that the term "Antique Sites" is what you are looking for. All these should have been announced in the Official Gazette, and therefore matter of public record. The General Department of Antiquities should have a register, as per art.3.3 , so I would naively suggest to call them and ask if they published it already somewhere, and if they can email it to you. As they are together with the Tourism department nowadays, they might be motivated by the argument that it is good for Tourism to have more information on Wikipedia :)
Out of curiosity, how many volunteers are involved at this point? What would be the language project that you would be using as your basis? (i.e. arwiki, enwiki?)
Please let us know if there is any way we can practically help.
Best regards,
Lodewijk