If your application calls stored procedure names have "xyz" in them, then there is no solution to your problem... When you rename the called procedures, the application will fail (because it will still try to use the old names that contain "xyz" instead of "abc").
Speaking from a SQL2000 perspective, you need to check "name" in sysobjects for tablenames, view names, proc names, etc. You need to check text in syscomments for sproc content, etc, you need to check syscolumns for column names, etc.
I'm sure for every place you catch, there will be 2 you don't catch.
I'm with GeorgeV, DO NOT DO IT. Let sleeping dogs lay.
Have you understood what the users here are telling you?
If you change a table name from xyzMyTable to abcMyTable, then all views, triggers, procedures functions, client side calls etc must be modified to point to the new name.
Or are you asking how to search for and change data stored in the tables?