Whats a good starting dirtbike?

I've been riding my friends dirt bike for a while and its loads of fun.... and i was looking into getting my own, i have $2000 budget and was wondering what is a good starting bike? Im 5'11 and 150 pounds. my friend told me to go to powersportsmax.com for a cheap starting bike, but those look like, well, flee market brands? Any help?