As Fleecewife says, fleeces are only any use to handspinners and other crafters if they are looked after properly.
Some Jacob fleeces are delicious and will be much appreciated by handspinners. Unfortunately a lot of Jacob fleeces are not particularly nice for handspinning, and spinners know that.
If you can take them to your local Spinners Guild (map of all affiliated Guilds
here) or other local spinning group, you will get some feedback on whether they are suitable for handspinning and how to skirt and wrap them for spinners. If they are nice for spinning, most spinners will happily pay £5 to £8 for a fleece in good condition, more if it's particularly nice fibre, well-presented.