I take it you're meaning something in the short tele upwards range? Personally I'd get fed up carrying most of these up that hill repeatedly.
Canon 70-200 F/4 Non IS - great lens, relatively small/light, very sharp.
Sigma 100-300 F/4 - I was impressed by this, bigger but with more reach. I intended to buy it with a 1.4xTC but the model they had in was damaged.
Canon 85mm f/1.8 - I shouldn't have sold this, it was absolutely great.
or for something smaller
Sigma 50-150 f/2.8 (I think Johnny has one of these, relatively it's tiny).
I've said this to a few people now; join talkphotography and stick with it for 30 days and 30 posts (or whatever it may now be). It's a very cheap and reliable place to buy used gear.