Take an Art of Exotic Dance, Flirty Girl or other strip-aerobics class. Some local dance studios also offer adult strip tease dance classes that are less about exercise and more about learning dirty dance moves.
Buy a strip fitness dance video and practice the moves it teaches you. Some popular series that feature dirty dance moves include Erotique Cardio and Carmen Electra's Aerobic Striptease.
Visit a local strip club or bar with go-go dancers. These are great places to learn dirty dancing first-hand from experts--the dancers at these clubs make their living from dirty dancing, so you'll be learning from the best.
Rent or buy the 1987 movie "Dirty Dancing," featuring Jennifer Gray and Patrick Swayze. The movie is full of dance scenes, and the final dance sequence is still seen as one of the most sensuous dance scenes of all time. This is a good option if you want to learn classier dirty dance moves.