I got certified last year in a group naui course in Maine. . . . . I'm looking for recommendations on places I might be able to go that would be good for doing 3 or 4 days of diving, to get my feet wet. Continental u.s., carribean, etc. . . . I was looking to maybe do this in April or May of 2014. . . . May bring the wife if there's things for her to find that she can do while I'm underwater.
I will echo the recommendations for Bonaire, followed by Roatan (Coco View) followed by Key Largo. The question about your wife is difficult to address, not knowing what she might like to do while you are diving.
And, recommendations that are offered have to be considered in the context of what YOU are looking for - a Caribbean vacation with some good diving, or some good diving that happens to be in a warm area.
If I only have 3-4 days, and am spending money to get to a diving location, I am going to spend the time DIVING, even if I take family. That means diving morning and afternoon, spending time with family in the evening - IF I am not doing night dives. So, my comments, below should be taken in that context. I don't go to the Caribbean for social life or cultural enhancement (although I find that Dominica, in particular, offers some interesting cultural opportunities).
Bonaire diving is about as easy as you can get, and as plentiful as you can get, and the conditions are usually very good - somewhere among the 80+ dive sites there is always a good place to dive on a given day. I actually find the airfare to be quite reasonable and the resort costs to be reasonable as well - I have been there for a week of diving for the last 6 years straight, and we pay ~$1600/person for airfare and a full week of accommodations and diving at Buddy, with breakfast included. I can't complain about that While I personally prefer, and recommend, Buddy Dive, there are a number of good operations on the island.
A possible downside to Bonaire may be what there is to do outside of diving. If your wife enjoys environmental tourism and outdoor activities, it is a nice location - the national park is beautiful albeit rustic, elsewhere on the island there are lots of places to see flamingos, donkeys, etc. You can ride horses, bicycle around the island, etc. My wife went for 4 years before getting certified, and enjoyed having a pool, her laptop, and books. The downtown area of Kralendijk has a good selection of restaurants, and a comfortable atmosphere.
Roatan - generally good diving, I think it is a bit better than the Key Largo, not as good as Bonaire. There is limited social life outside of diving. Some of the best horseback riding I have done in the Caribbean was on Roatan, and the worst case of Montezuma's Revenge I have ever experienced was on Roatan. Coco View is VERY easy diving, nice laid back atmosphere.
The Keys are nice, Florida is the US so there is some sense of cultural familiarity which may be reassuring. But Bonaire in some ways is almost easier to get to than the Keys (unless you are driving yourself to the Keys, in which case you are simply looking at a LO-O-O-NG, BORING drive). You can fly into Miami, for example, rent a car and drive to the Keys, but that is still over an hour's drive. I have dove Largo for many years, and it is fun. I would personally go out with Rainbow, with Ocean Divers, with Conch Republic, with Amy Slate's etc. I have had very good experiences with all of them. I do not think there is really a whole lot to do in the Keys, either although there are some good restaurants, and I enjoy the laid back ambience. A drive down to Key West is a nice activity on a day you get blown out by weather.
The diving in Coz, the diving in Belize, etc, is good. I don't care that much for the atmosphere, so I don't go there any longer.
