In reply to R4chC:
I feel your pain; I wear UK 2.5 in street shoes! The good news is that most climbing shoes do come small enough. The bad news is that no-one stocks them and shops are often unwilling to order them in because if you don't take them they are hard to get rid of.
I find that most 5.10 shoes fit me pretty well. I have been wearing the same model (Anasazi vcs size 2) for about 8 years now because I know I like them so I can order them from shops that know me on the understanding that I will take them unless they are faulty.
I have found that you are most likely to find small sizes to try on in shops that are located at climbing walls. I guess they have more children coming through than shops on the high street.
Good luck!