Um, well it really depends on what type of fiber you want....
Certain types are going to cost a bunch more than others.
I am spinning up some pure Angora rabbit right now, take a look on Etsy and see what the price per skein on Angora is, it's high. Alternatively, go look at the price of an Angora sweater, some are over $500.00.
You're looking for wool? What type? Pure wool or with something else blended in? Something fancy or plain? A solid colour or a handpainted masterpiece?
Most things artisan or handmade are going to be costly, lots of time goes into it. My finished Angora yarn will have taken a ton of my time (and money) to make, all of the feeding/cleaning/grooming the rabbit, then the hand plucking of the fiber itself and finally the spinning into yarn. Then if I decided to dye it or not. You must take into consideration that alot of these people are raising the animal that the yarn came from.
When you start to break it down it can really vary...
What's your price range and how much do you need?