How do I get rid of an extra page before printing on an excel sp.

I have multiple pages on multiple sheets on excel. Pagination is set up
under Custom Footers. An extra page prints at the end of each "sheet", thus
throwing off the pagination of the sheets that follow. How do I print only
those pages that contain information?

You need to work out why it is printing blank pages. By default, it wont do this. Try going into page break preview mode so you can see where the blanks are coming from. You can drag the boundaries in this mode to remove the blanks

Matt