Zoom lens for EOS 400d???

Hi there.
I was just wondering what people's opinions were on which zoom lens to get to with a Canon 400d? Assuming I get the 18-55mm lens, which would be the most user-friendly and good quality low to mid-range zoom lens to buy in addition?
Many thanks in advance.

What is your price range and subject matter you'll be using this for?

Canon's "white" lenses are popular, though on the high end of the price scale.

Was thinking £150 - £300 for a lens that will get me in close on faces about 15-20m way. I was thinking of getting an 18-55mm as my standard lens plus a zoom as an extra, but am I better off just going for an EFS 17-85mm as my one and only lens? I need to be a bit flexible (might get a non-expensive wide angle too).

What do you think?

Many thanks!