Working with Macros

I am working from an original file that has four-five columns of product IDs, these original columns must be reformatted into one column with four-five rows for each individual listing. This is a fairly large worksheet and would be far more tedious than I would like to copy and paste each entry, so if there are any suggestions for how to speed up this process that would be great.

Attachment one is the original file. Attachment two is the altered file which has been started to get an example of what I am trying to do.