This is my first attempt at something like this so it's not terribly creative as it's just artwork used from the LOTRO website, but it stays with the theme of the game.
There are three colours in the file that you can choose from. Normal, blue, and green. I hope you enjoy it... or at least one of the colours.
Plus the idea of having the two bars together was from Caldric's Stone Age Bar. I liked it and used the idea.
Update 1.1
I've coloured more of the tabs, buttons, etc to match the appropriate colour of each skin. A red skin has now been included as well.
Update 1.11
Fixed a small border of the green skin that showed up red.
Edited the XML to the right version. (Thanks Ernest and Dolby

)
Update 1.12
Changed the social highlight graphics. It looked good when highlighting people on friends/kinship list, but looked terrible for highlight traits from the character journal.
A couple of people are unfamiliar with moving the UI bars to align with the skin and Caldric's directions are perfect for it:
To do so, once you replace the skin, you want to follow these steps:
1) Open your Main Menu
2) Go to "UI Settings"
3) Go to "Quickslot Bars"
4) Select the Bar you wish to use (1-5)
5) On that Bar, check "Always Show" and make sure it's not docked
6) Add an Ability to that bar (for alignment purposes)
7) Use "Ctrl+\" to unlock your UI
8) Drag the Quickslot Bar into the Bottom Bar graphic and align it
9) Lock your UI and you're ready to go!