I always look at department stores -- Macys, Nordstrom, etc. At Macys, you can usually score one on sale and with a coupon. I think mine is an Anne Klein coat, and I also have had DKNY. I've always spent in your price range or less.
Jcrew used to have nice winter coats, but I think are more expensive than $150-200.
You can also score a lot of the same department store coats for less (I sound like a commercial) at TJ Maxx, Marshalls, and even Overstock.com.