Like @Thimes’ suggestion, I am also partial to the local Chinese Spaghetti factory dumplings. I cook them like mini-potstickers, so that the bottom skin gets crispy.
For the non-pan fried kind, if you have an Asian market in your area, I like the Wei-Chuan brand of dumplings (non-soup dumplings). They have quite a number of variety, and I’ve generally found them to be pretty tasty, especially the “hand made” and “Beijing style” lines. I personally have never enjoyed any of the frozen soup dumplings, as they don’t even come close to half-decent soup dumplings you can get at a restaurant.