How can I report an individual who has a crafting company out of their home without a vendor's license and is not paying taxes? She uses PayPal and debit to charge her customers so there is a pattern of her selling the crafts.
Does this individual's work cause problems in your neighborhood?
If so, you can report suspicious or fraudulent activity to your local police and they will investigate.
As far as reporting them for not claiming this income I guess the first question would have to be: how do you know this?
There are numerous ways to have knowledge of this so that does not have to be a problem but it would have to be addressed.
You can report someone anonymously but the IRS requires 'certain' information before they will investigate a report.
The IRS has forms that must be completed when someone files a report and, usually, it will take months/years before a claim is finalized.
If this happens in the USA, there is a Form 3949-A (Information Referral PDF) to report tax fraud:
www.irs.gov/
If she is not paying taxes, you could notify the IRS.
This is a job for legal authorities (IRS) , that's all you can do legally, anything else may end up in some type of conflict.