There's a LOTRO tab on this site that has a server status bit: http://motty.000space.com/
If that says the servers are up and you still are unable to connect, then make sure you are either using a new account created from the lotro.com page (via that 'play for free!' sidebar thing), or a turbine account that was used to play the retail game in the past. An old beta account will not work, for example.
It worked for me last night. Haven't tried this morning but it probably would. --- Q. If your canoe is in a tree with its headlights on, how many pancakes does it take to get to the moon? A. None. Snakes don't have armpits.