If you plan to be serious about this (as it seems you want to be), you'd only need the DBA if you plan to set up a business name. You could be a sole proprietor, in which case you would not need a separate tax id number. Personally, I'd suggest trying to go for a LLC taxed as a sole proprietorship as it would help shield you from personal liability beyond the business should things go south. If you're a sole proprietor, you can end up risking your house and other assets. Crafts don't tend to be something people sue over, but you never know.

You may want to contact the SBA (Small Business Administration) or SCORE (Service Corps Of Retired Executives). What sort of crafts are you planning to make? You may also want to check out etsy.com to sell on. Best of luck!

Keeping in mind I'm no expert, I've read in multiple places that if you make less than $5,000 a year you don't have to pay taxes on it. If you'd like to set that sort of thing up and be kosher though, all you really have to use is your social security number, you don't need to get a separate tax ID number.