I think people often say "accent" when then real mean to say is "dialect". I'm not terribly proficient in imitating dialects, but I think my version of a Harlowite is spot on. If you think you're a master dialect impersonator, you must visit the speech accent archive. For fun, you can listen to various dialects to see how close they come to your interpretation.
The site compiles the way people from all over the world recite this English elicitation paragraph (which contains most of the consonants, vowels, and clusters of standard North American English):
Please call Stella. Ask her to bring these things with her from the store: Six spoons of fresh snow peas, five thick slabs of blue cheese, and maybe a snack for her brother Bob. We also need a small plastic snake and a big toy frog for the kids. She can scoop these things into three red bags, and we will go meet her Wednesday at the train station.
Give it a try. I'm inclined to record myself and submit it to the site, so that a true, not stereotypical, Newfoundlander can be on record. Illustration by James Collins.