I think the Kobo would also be good for library use in the UK, which is slightly cheaper than the Sony PRS-T1. You should check out the Kobo & Sony forums if you're going to consider one of them.
In the meantime, while you are saving some cash, there are plenty of free ebooks available, not just old classics, check out
http://uk.kinlib.com/ for links to the current freebies on Amazon. Plus, there's the stickie at the top of this forum "FREE (and bargain) books for the Kindle". By the time you've read your way through that lot, perhaps library borrowing will be available for the Kindle anyway. <fingers crossed>