Okay, my problem is complicated. I purchased a pre-configured site from a Canadian Norwex consultant. I live in Ohio in the US. The site was initially configured fine for all the different Canadian provinces and their sales tax set up. However, there was only a 5% flat tax applied to the US sales at the time, because she was selling from Canada to the US. The company itself is in Canada, so tax is charged based on the shipping address, not the billing one.
1. Do I need to go through and configure the taxes for each of the states separately?
2. If so, what do I label it as in the Tax Classes (following the ZenCart tutorial where it does the set up for Colorado, I set one up for Ohio but it doesn't seem to be working).
3 Is there some way I can apply the change in class across all my products or do I have to do it individually?

Sorry for all the questions. I'm obviously new at this and reading all the tutorials and FAQs and several threads on here just got me more confused than when I started! Thanks!