Most vet books cost £50-£100+ when new so aren't cheap and are very specialised (e..g 500 pages on anatomy only). Unis don't expect you to be a vet student already so try not to get too keen on learning random vetty facts - the internet is more than adequate for learning about interesting diseases you may have already seen and is also FREE. You will learn more from placements at this stage.
Perhaps reading about scientific developments in the vet field is a good idea. Or websites like
http://www.vetsonline.com/ and DEFRA, Farmer's Weekly.
Well all you can do is try your best and identify any better ways of learning/revision sooner rather than later. Depends what you mean by 'waste of time' - I would say it is a useful/interesting learning experience regardless....
Yes. Liverpool allow you to put work exp up to December (and 10 weeks is the
bare minimum you should be looking at getting 15+ for Liverpool) but the general rule is that you should have at least the minimum before applying, and ideally more than just that.
Hope this helps.