Reading all rows in multiple dataset tables

[cashdeskmac]

I have a form with 7 datagrids, each on a seperate tabpage and reading from
it's own dataTable. I would like to take the first three fields of each row
and show them in a listbox (for example, ID, first name and last name). I
know how to join them to create a single string and how to add them to the
listbox items collection, but is there an easy way of reading every single
row in my dataset, rather than reading each table one at a time? I seem to
have to use the same code 7 times just to add, delete, update or query the
data I.E query the Manager table, then the Cashier table, then the next, etc.