The Camden Art Market is closed for the winter, but should be starting again soon - this takes place once a month. They have
a facebook page; if you're not on facebook, you can google and find information.
The gallery crawls are *great* opportunities to see & purchase art - though most galleries are open every day! At the crawls, more people will be out, and like XcapefromNJ pointed out there are street vendors, etc. And usually free wine!
NoDa has a gallery crawl the first & third Fridays. SouthEnd has a gallery crawl the first Friday of every month - not sure if they go through the winter, NoDa does. I thought I'd heard of Uptown Gallery Crawls, too, but I don't know when those are.
Like I said, you don't have to wait for a crawl! You can visit a gallery any time & view & purchase art. There's a range of prices. I don't know of a singular place that lists the galleries in Charlotte; it might be fun to google & pick an area to go to & explore.
Pura Vida Worldly Art often carries local artists' work, and they're right there in NoDa now, so you could zip into those galleries, too.