Value of columns inOracle tables
You can generate an SQL script with sqlplus and run that.

spool /tmp/get_the_ed.sql
select 'select ''' || owner || ''', ID from ' || owner
       || '.' || table_name || ' where jn_osuser = ''Ed Spencer'';'
  from all_tab_columns where column_name = 'JN_OSUSER';
spool off
start /tmp/get_the_ed


You need to replace "ID" by the primary key of those tables.  If that isn't always the same, you can go for rowid.