Can anyone help point me to references regarding building a single pivot
table from multiple data sources.

For example, If I have two different worksheets that have a common data
field that can be used to correlate the two sets of data, can a pivot table
be built that uses both sets of data?

What about if one set of data is in a database and the other set of data is
in an excel worksheet?

I don't have control of the external database, so if I need to pull the data
together 1st, before making a pivot, then I would have to create another
database of my own and import both sets of data. Is that the recommended
solution?