If you are an intern or working in another specialty and are interested in anesthesia, you should contact programs. Obviously, the most straight forward approach is through the match. However, I have noticed through discussions with others and watching my own program, that there are sometimes opportunities that are aren't made public. There is always the "in house" politics of residents leaving, being excused, etc that may open up spots. There are also programs who have been approved for expansion who may be able to apply the expansion to current classes. The only way to hear of these opporunities is to ask. Get your CV together and start making contacts. You might be surprised with what you will find (ex Yale dude).