If you can get out of the city (if you are going to Halifax)find your self a clam shck and have your self a fried clam feed. Also out side of the city in Peggy's Cove, worth the trip even if you get a bad meal just for the beautiful view. There you will find plenty of Sea food places with very cheap lobters, Especially in American dollars. In Halifax proper(Oh actully he has stands all over the maritimes look for one) don't forget to visit Pete's Frootique. That is founded by Pete Lucket, Canada's National Treasure. He is the Traveling green Grocer on the Food Network. He is quite a character. Many of his shops are run by his relatives such as his brothers and nephews and they also are characters. He sells wonderful produce including Nova Scotia apples that will be just beautiful this time of year. Try a caramel one they are a great treat. He also carries dulse which is a local favorite. Dulse is a sea weed harvested from the Bay of Fundy. It is an aquired taste but a speciallity of the region. The locals eat it out of bags like popcorn. Even when I was a local I didn't do that but I always made visitors try it. Pete also carries a favorite treat of mine, Montreal bagals. These are bagals made in the wood ovens of Hasidic Jews in the heart of MOntreal and flown in to Pete's on a regular basis. The wood oven makes this a bagle like no other.
A place in Halifax I miss is is called The Daily Grind and is a coffee shop and magazine stand run by the large Budist comunity that is situated in Halifax. They have excellent coffee, great desserts, local art, and all organic products. This is the ulimate anti star bucks expereince as it is run as a nonprofit.
The maritimes in general is not a place that has taken to the chain resturants. You will find fewer Denny/Perky type places there. You will find many Mom and Pop places that have homemade meals for you with daily specials and fresh gramma made desserts. You will find clam shacks and fall suppers with lobters and mussels or turky and stuffing.
Try going to a farmers market. Halifax has a really great one just beside the harbour. If you go to Wolfville or Truro, or Luninburg they are all very roadfood friendly all have famers markets.
I havn't lived in the Maritimes for five years and I wish I kept a record of the places we frequented. It is an untaped resource for roadfooders. It is kinda like Canada's version of the South as it has regional accents, regioal foods and really great regional music.
I envy you and wish I could go there right now. My partner has applied for a job in Halifax and I hope he gets it. Have a great time, I hope this reaches you in time and you have not left on your trip. If I could be of any other service you could email me directly.