Is there a smoking area at the airport or can you smoke in the restaurants and bars

No smoking in restaurants or bars. You can smoke in a seated garden area directly across from airport terminal. I can't remember the exact door number to exit ,but it is close to the American Airlines Check-in area.

Here is a map of the smoking areas pre-security. http://www.miami-airport.com/library/map-smoking-areas.pdf Post-security there is a smoking area across from TGI Friday’s, near gate D34.

Exactly

Smoking areas are located outside the terminals on Level 1 (arrivals) and Level 2 (departures) across the street from Concourses D, E, F, H and J, and inside Concourse D at the TGI Friday's smoking lounge near Gate D-36