Method 1:

Install Lotro in one folder, then install Lotro into a different folder.
Start each Lotro from there specific locations and you should be able to dual log with 2 accounts.
Have done it on 2 different computers with 2 accounts.


Method 2: (may be nerfed already)

Load LOTRO and enter username and password and press login
Then select server and press play.
All you do now, is while the first game is about to load, double click your desktop LOTRO and load the second account.
Note: You should have a decent comp to run this with 2gb of ram and run games in windowed mode.