Hi kimbo,
You have a single Spreadsheet, containing three Sheets, each of which apparently contains one Table.
IF the Tables are independent of each other, you can easily select one of the tables, Copy it, then Paste it into a new (and empty) Numbers spreadsheet Document. This will create a new spreadsheet, which can be emailed.
IF the Tables on the three sheets of the original document are inter-dependent (Information on one sheet is collected by another, and used in the new location), you will not be able to separate and email a working copy of the Sheets with working copies of the Table(s) on that sheet.
You can, however Select and copy that table, move to a different location (Sheet), then use 'Paste formula results' to create a static copy of the copied table.This copy may be copied and placed in an email.
Regards,
Barry