Erle Stanley Gardner 
Spill the Jackpot 

Bertha Cool has just been released from a sanitarium where she has been recovering from flu and pneumonia, but soon she and Donald Lam are on the hunt for a missing bride-to-be. They become tangled in case filled with slot-machine skullduggery, a double-crossing client, murder and a spot of financial finagling before they eventually achieve their goal.