I've spent nearly all my life in Michigan, up near Canada, and since we're surrounded by the Great Lakes, we're a little more isolated and some of our words are different from the rest of the USA. We say "pop" instead of soda, we also say "crick" instead of creek. It wasn't until I was a teenager in our capital Washington D.C. that I was identified as having "a northern accent." Two days later, I was at a fast food restaurant on the east coast and asked "What kind of pop do you have?" The lady said that they didn't sell popcorn.
While meeting my brother's in laws at his wedding last summer, just to be a jerk I put on a thick "Yooper" accent, which sounds a bit Canadian without prepositions, and my brother's new sister-in-laws kept asking him "Why does your sister sound like the sheriff on Fargo?" (A movie that takes place in North Dakota near the Canadian border).
The US southern accent is definitely "Twangier" than others. Just wait until you hear a great "Boston" accent, sounds kinda like a flat, garbled British accent
Bantimna, if you ever get a chance to watch the TV show King of the Hill, an American animated sitcom, watch it. It gives a good range of US accents from hillbilly Texas to Southern to Upper Midwest (sounds like Canadian)