Louisiana was owned by the Spanish and the French during the time you are looking for your John Perry. The Spanish took very good censuses and perhaps you will find your John in them. We did not buy Louisiana until 1802/3? Further, when we did buy it we had no idea what it was beyond land nor did we know who lived there; so even after that you will have to depend on local (parish) records for land onwnership and church records for marriages and such. Good luck cathryn in northwestern Nevada