Searching user table using user ID

 I know I can access the currently logged in user id using this
 MembershipUser currentUser = Membership.GetUser();
done using asp.net sql provider, in c#

 

say I know the user ID of a certain user, and I want to use this ID to search anoter table and return a string for the home address corresponding to that user ID, how do I do it? thx.

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