Get Product by SKU

Sometimes you need to find the page id of your product simply using the sku. I ran into this when I had to build a backend inventory manager which updated Receiving and Sales figures based off of some spreadsheets.

Stolen from: http://www.skyverge.com/blog/find-product-sku-woocommerce/

NOTE: The site I was working with was actually a Marketpress site and not a Woocommerce site. I ended up modifying the code from skyverge a little bit to fit my needs. Same idea.