Go to Royal Oak---12 miles northwest of Detroit. Or else, to Greek Town, right in Detroit (for a tiny sliver of ethnicity).
There are some good blues bars around here too: Sisko's, in Taylor. Or Memphis Smoke in Royal Oak. Or Ted's bar, in Clawson.
Dress Code: Its pretty blue-collar around here. No one will judge you harshly for being under-dressed. People are slobs here. Detroiters like to pretend they are a 'world class city'---as if saying it over and over, mantra like, will make it so. The blues bars are, of course, very blue-collar---t-shirt and jeans will do.
You have the choice of 4 casinos in the area. Detroit has the Greektown Casino, The MGM Grand Casino, and The Motor City Casino. You can get to the Windsor Casino in about 10 minutes by going through the tunnel.
If you want to stay in downtown, hit Greektown. There are several restaurants with bars, the casino, Marilyn's on Monroe (my personal fav), and the Music Cafe which has live music nightly. There are also a few dance clubs in downtown if you like Techno. One is called Club Blue. Not to far away is Royal Oak which has some good nightlife.
a nightclub/dance club
It's a huge gay bar, but lots of straight singles and couples also go here because it is THE best place to dance and listen to the NEWEST dance music in Michigan. It also has some of the best people watching outside of New York, Atlanta, or San Francisco.
Dress Code: anything goes, casual, 1/2 naked, semi-formal, etc...
Chic design, incredible sushi, some of the world’s finest techno. Even if you don't like sushi or techno, the beautiful interior and great atmosphere is worth checking out.
Dress Code: Dress as our soul desires.
Also check out the DEMF (Detroit Electronic Music Festival). Since Detroit is the birthplace of Techno where else would you hold an annual festival?