Vice Admirals and Rear Admirals are addressed as "Admiral".
There are several types of vice admirals and you would address them as such. For example you would address a rear vice admiral in a letter as Dear Rear Admiral.
I'm not sure of the 2009 figures but back in May 1805 there were 144 Admirals consisting of 46 Admirals, 36 Vice Admirals and 62 Rear Admirals.
A constellation of Admirals.
Nelson Admirals was created in 1967.
Amsterdam Admirals ended in 2007.
Amsterdam Admirals was created in 1995.
Norfolk Admirals was created in 2000.
Cork Admirals was created in 2002.
Admirals Beach's population is 185.
Greenwich Admirals was created in 2001.
Admirals Beach was created in 1805.