I think that depends what you mean by post war of the lance. There are couple time frames i can think of that fit.
Pre Age of mortals - Same rules as exist in the Dragonlance Adventures book These are written circa 1ed-2ed. The 3rd ED Version I didnt really use I leafed through it and did not see anything useful to me at the time but DL is probably my favorite D&D Setting so I did not really need most of its back grounds. The 4e Version is planned but not released yet but DL Nexus has info on it.
Age of Mortals
There are some good reference material in some of the old Dragon magizines but I do not have references to exactly where. If you are looking for something more specific let me know I can probably point you in a direction.
Dragonlance Atlas
This is a great book for the area. Has good information on a lot of towns and villages. There are versions for different periods but my version is pre AOM so i dont know if there is a revised with that part.
Leaves of the Inn of the Last Home
This is an essential for any true dragonlance collection. It has good information on different areas (mostly post WOL pre Legends) but more importantly it has the recipe for Otiks spiced potato's... OMG they are as good as promised by the books :p
History of Dragonlance
Pretty rare collectable book. Really just rehashes things from the book but if you are not like me and havent read every dl book then this is a pretty good cliff note type.
The best reference is the books. Sometimes the contradict (like Sturm fighting draconiains in the preludes) but they add good reference for the area and its people.