The casino used to portray the "Frost Casino," is actually the Riverside Resort and Casino in Laughlin, Nevada, right across the Colorado River from Bullhead City, AZ.
It's often mentioned that Poker Face is loosely based on Columbo of the 1970s. In this episode at 46 minutes, Natasha walks into a casino bar and one of the slot machines plays a digital version of the song "This Old Man". That is a tune that Columbo often hums or whistles in several episodes.
The episode's title, "Dead Man's Hand," refers to a poker hand consisting of a pair of aces and a pair of eights (usually, but not necessarily, the black aces and eights). Legend has it Wild Bill Hickock was holding that hand when he was killed.
Sterling calls Charlie "Encyclopedia Brown". Encyclopedia Brown is a series of books featuring the adventures of boy detective Leroy Brown, nicknamed "Encyclopedia" for his intelligence and range of knowledge.