My bookkeeper informed me that I needed to start claiming/paying taxes if I make over $250 a year. I didn't my first year of crafting, but the second year exploded!
I live in NC and I got a tax id number easily, for free, online. I also registered my company name & filed taxes. I also need to register in the county seat if I want to participate in large fairs/shows. I haven't done that yet because it's $250. I can wait until I'm making the big bucks!

It's been scary doing all this legit stuff but so exciting & rewarding.
It may be different in your state, but I would at least start inquiring once you make a couple hundred bucks.
Good luck!