Display records in order of distance from post code

 Hi,
I'm developing a search feature which allows users to search for other users by distance using their post code (UK only). How can this be done? For example:
Dim MyPostCode as string = "AA1 1AA"

Select * From Users Order By [PostCode] Nearest To " + MyPostCode
 
Obviously the above code won't work at all, but its the kind of thing I'm looking for.
 Alternatively if you know of a better method that would also be appreciated.
 
Thanks,
Curt.

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