first main question i'm getting is how to set up labels. i'll go into more detail but for starters here is the MS instructions for how to print labels via mail merge
http://support.microsoft.com/kb/294684
when you put a number in the labels field in "Add to or change my Stash" form and save the record, this collects in a table for later use.
when you export to excel it creates a spreadsheet that automatically has multiples based on the numbers you input - you dont need to adjust the label numbers or fiddle with the spreadsheet at all - you may want to add a date field so you can print that on your labels but thats up to you.
create labels as per the link above and use the spreadsheet as your data source when prompted, arrange your labels as you like and print.
when you're finished, make sure you clear the labels by clicking the "Clear Label Print List" button or they will be duplicated the next time