my fiance he aslready recived a conformation about he file last august, but until now i never recived a letter from embassy for our finace visa, how many months to process all the things need to get thier, how mnay months to eb eaxact, plssss help

my fiance is from las vegas then he start file to be exact is july22,2011 then until now i never recived a letter from embassy?how many months should i wait the letter from the embassy i cant wait to get thier to my one and only love carl, i miss yoouuu so much