So off I went exploring hills and valleys and ruins, admiring the pretty scenery, and here's what I found ...
Tyl Annûn (Annúminas)
Funny story ... while Myndariel was searching through Annúminas, she fell off a high ledge and hurt her leg landing on rubble below. She turned around and looked up in time to see her saber-tooth cat hesitate at the edge and then jump off, legs outstretched and mouth open as if screaming silently. I imagine he was thinking as he fell, "Aaaaahhhhhh .... this is gonna hurt!" Poor, brave pet!
Barandalf (near Whitshards)
Tyl Ruinen (island to SW)
Tyl Ruinen (main island)
Tyrn Fornech (near Rantost)
Barandalf (across river from Dwaling)
I admit, I had to check the LOTRO Wiki on where to find that last cache in Barandalf. I had visited the eastern shore of the Brandywine River, but further north near Barad Tharsír. Still, it was fun finding most of them myself, and Myndariel completed some deeds, reached kindred with the Wardens of Annúminas and finally got the mount.