Go hunting! Any critters that would normally drop some sort of loot will have a chance of dropping a treasure map. Explicitly, any critter from which you might normally acquire a runestone or a fancy item.
If YOU had a treasure map that reminded you where your loot was buried, would YOU leave it hanging casually out of your pocket or would you lock it in a box?
Maps are not weighted to be more or less common based on for any particular level of creature. Just remember that they're not extremely common, so don't get discouraged. Just keep your eyes peeled.
Why yes, it is. :-)
Absolutely not. Get out there and explore! Treasure hunting may be lucrative but it isn't supposed to be easy! Break out of your usual "grind" and have some fun!
Check your experience when you first find the map!
Nope! Maps don't expire. If it's hard to find, grab a friend or two to help and keep looking!
"If you think your treasure is in those hills, you can always go back to it when you've got the skills."
Some of the areas they lead to are more difficult than others. It helps to know some lore of the different areas!
The maps are REALLY PAFO-heavy, and that's intended - they're not an important system and they're totally usable without knowing all of the details. So … nope :-)