On Multibit, one of my transaction to Bitstamp is not confirmed since 5 days (Status icon displays a white square). Apparently the 0.0001 fee was paid. I don’t know where is the money neither what to do.
By the looks of things the transaction never made it to the network from your client. Find the "reset blockchain" button in Multibit and wait for it to recover. You won't lose any funds (the ones you "sent" never left) and then you can give it another shot.