Lima [1] is overflowing with casinos, though the most reputable ones tend to be in the major hotels. Wherever you go, do not play the slot machines, as they tend to be rigged. Some casinos open in the evenings and close around dawn. Others are open 24 hours a day. Regardless, they usually offer free drinks, food, and cigarettes to those who are betting.
Better casinos include the Hotel Sheraton (Paseo de la República 170, tel. 01/315-5000) in central Lima [2].
In San Isidro [3] there’s the upscale Los Delfines Hotel (Los Eucaliptos 555, tel. 01/215-7000), with minimum US$5 blackjack bets.
And in Miraflores [3], the Stellaris Casino at the Marriott (Malecón de la Reserva 615, across the street from Larcomar, tel. 01/217-7000) has minimum US$3 bets at the blackjack tables, and Best Western’s Casino la Hacienda (28 de Julio 511, tel. 01/213-1000) also has a minimum US$3 bet.
Links:
[1] http://www.moon.com/destinations/peru/lima
[2] http://www.moon.com/destinations/peru/lima/sights/central-lima-and-pueblo-libre
[3] http://www.moon.com/destinations/peru/lima/sights/san-isidro-and-miraflores