I recently had weight loss surgery and am now down into the size range of normal shops. My go-to when I was still plus-sized were sites like womanwithin.com. You can get great basics (which is about all I wear) for very little money. And their selection is rather large, with the same garment in lots of colors in addition to many different styles available.
So what's the normal-sized equivalent? Whenever I google 'inexpensive women's clothing' I get lists of sites that have t-shirts starting at $25. My best bet so far is Old Navy, but I'd like to find even more options. And I do shop resale shops fairly regularly.