want to get username,databaseName from database and store in a result set(DataTable)

hi
 i want to get  username,databaseName from database and store in a result set(DataTable). that query need to check get userName , databaseName from Multiple Databases
1 database having A table in this table 10 user,
2 database having b table in this table 10 user
like that so on.
that query result store in dataTable. with name like
UserName-----DataBaseName
a                            1401A
b                           1401A
b                           1401B
c        ...