There are a couple different ways to find angel investor groups. You can either search online or ask your local Chamber of Commerce.
If you search online, a good place to start is with the Angel Investment Network (https://www.angelinvestmentnetwork.net/). This site provides a directory of angel groups around the world.
Another good place to search is the website of the Angel Capital Association (https://www.angelcapitalassociation.org/), which is the trade association for the angel investing industry.
Asking your local Chamber of Commerce is also a good way to find angel investor groups. Chamber of Commerce staff can usually tell you about any local angel groups, as well as provide you with contact information.