Build a sheet that can “query” another sheet and show a subset of the data.

Specific example:   I have a 3000 row table of Stock data.  
I want another sheet where I can type in a small number of stock tickers and have the sheet read the big table to show only the stocks I want.

(We will do this one a couple of ways:  AutoFilter.   Match & Index.   )

 Grouping data by Date in a Pivot Table.

 How to build something into a workbook that lets users know that Excel Macros must be on.

This one is tricky.    My only idea at this point is to have a big red error message on the sheet that an AutoOpen macro will turn OFF.

(An AutoOpen macro is a macro that runs when the workbook opens).

I