I remembered a coworker, Nicole Cassamassino, telling me about a chrome app called PDF Mergy. (click on the link to check out the app in the chrome webstore) Basically, you can upload PDF files to the service and it will magically merge them together into one file.
What I liked about this chrome app is that you can upload PDF files either from your computer or from Google Drive. I also was able to upload a Google Document from my drive (that was not a PDF file) and it converted it to a PDF right away. Once you have uploaded all of your files, you have a choice of having the merged file saved to your computer or to your Google Drive.
So, if you are interested, here are the steps
1. Add PDF Mergy app to your Google Drive account - choose Connect more apps under the Open with drop down menu when you are viewing a PDF in your Google Drive Account.
2. Go to https://pdfmerge.w69b.com or choose PDF Mergy under the Open With drop down after you connected to your account and are viewing the PDF that you want to merge with another PDF file.
4. Upload all of your files. Then determine where you would like to merged file to go.
It was very easy and quick to use! I know that there are many different ways that you can merge PDF files. I only used this one seeing as though it was recommended to me one day.