CPA Technology Advisor takes a look at sales tax products for various ERP systems including Dynamics GP and a couple of products that have long supported GP come out on top. Notably Avalara and CCH’s products. If you need help navigating the 10,000+ sales tax jurisdictions in the U.S., you can start with this article.
CPA Tech Advisor, Sales Tax and Dynamics GP
Archived post from 2008. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.