A server merge occurred some time ago. TNF announced that they would close inactive accounts until they were used again and that these accounts might be reset. Don't panic though, I think if you send in a support ticket with the details, TNF might be able to help and get it all back for you. This is what they'd said around the time of the Server Merge.
On the login screen for NF's game, you have a message saying where the servers merged.
I believe it goes something like "NEBRASKA= Iowa + Yamato" and "KAISER= Nelson + Bismarck"...I'm not perfectly sure as I don't have the NF client running in front of me but you can check this under annoncements when you go to log in to the NF game client.

barracuda is right

nebraska = iowa and yamato server
kaiser = nelson and bismark server

and i don't know whats the older name of each server cause just started here almost 1 year, but i do remember i got older account, i think it was from new york server -.- or i forgot,

and if you can't find your ship in both server, try to send ticket to reactivate your account due to your long inactivity, rest assured that if you got prem ships or other prem stuff it will be safe...

welcome back

Also in Feb 2010 a new server was added - Nelson, at this time the old servers were renamed:

New York - Bismarck
Missouri - Yamato
Arizona - Iowa

So what was Arizona and Missouri is now Nebraska
And what was New York has merged with Nelson that you probably never knew and become Kaiser.

if you still cant find your stuff but also remember to check your HQ and if you had any prem ship or Event BB you have to re-select it from items also your account may have been closed if so send support ticket to re-activate your account

Your items may be in storage.

please submit a ticket to support with as much information as you can.

ie server, date last played etc.
In most cases items can be recovered if the absence is not too long.