How do I match 3 different workbooks information for similar data?

I am working with 3 different workbooks that contain some similar data. I am
trying to find a way I can match up that data in a separate workbook. The
first workbook I pull off a website, the other two are also pull out of a
company website. These three sites give me a option to save as excel
spreadsheet. What is constant in these three spreadsheets is the PO number,
part number, some times a date reference. Its very time consuming, being I
have to perform this on a daily basis. What would be the best way to get this
done.