There is a night club within the resort but it really hasn't drawn the large crowds yet (only when the hotel is really busy or when there are alot of Dominicans during the weekends). Drinks are not free in the club but recently, they have been allowing women in for free and giving them drinks for free too. Not sure if that will change. I also think there is a $10 charge to get in.
Next door, there is an other disco called The Hurricane that draws more people. Say hello to the Adela the waitress (she's a great woman!!!).
If you like DR music, then try to go to La Barrica and the Orion. I'm not sure if the Orion is open every night, but it's probably best if you check it out during a weekend.
Playa Dorado also has another disco called The Crazy Moon. Worth a visit too. Not sure if the other disco will be open because it is currently under renovation (Andromeda).
Try to make some friends with some guests while staying at the resort, and make plans to head into town together (share the cab ride).
Also, make sure that the hotel gives you a room in the new section (not the old section - the original EMI resort). The hotel is beautiful but be warned that there are many stairs to climb. I've never stayed at the resort, but my fiance works there and I have many friends who still work there. When I'm in town, I visit often.
Bring an umbrella in case in rains. And a good flashlight.