Ok, so you have a users table and an address table?
How are you relating the address to the user?
there should be a column in the address table that creates a relationship to the user that the address belongs to, you would need to create a joined query using this relational column and add the where clause using ckey query sting variable.
See the following page for details on creating a join query to get related information from 2 tables:
sql_join.asp