what style is this ?

I am looking for music that I have heard on various tv
programs. It is usually in movies or shows that take place
in the speak-easys' during the prohibition period. They usually are female singers backed by a piano or small band.
The singers are the low sultry voice types in slow to medium
paced songs. The most recent example that I can think of is
an episode of 'Sliders' where they were in a world that had
outlawed caffine. Remi was playing the piano for a black
female singer that sold caffiene in a speak-easy and also sang. This kind of music is what I am trying to find on CD. Can anyone help with suggestions, please ?