i dont know TX land prices
but $20k for hundreds of acres is a stretch,
first i would look at the market and see what rural land is worth around there
few things that cost extra,
location, anything near a city/highway/metropolitan area will cost more,
features such as water, meadows, views will cost more,
if the land has been worked such as farmland will cost more
if cant find size at your price,
look for a smaller lot that borders state land,
even a 5 acre lot bordering stateland can give you access to those lands and almost as its your backyard.
if your looking strictly for hunting, may be interested in a landlocked parcel with easement access, those usually cost less as access is limited, some dont want the possible legal headaches that come with easements, but for less $$$, might be a consideration,