These are some of the products I personally use and recommend. (I am not paid to recommend them.) I just like sharing information about great things that get the job done.
The ingredient behind professional-looking bags
While you can't see the interfacing on the outside of a bag, you can certainly appreciate the difference that interfacing makes to the finished outcome of a bag. Simply put—good interfacing is the secret ingredient behind the successful finish in a bag. I use many different types of interlinings and interfacing in my bags from different brands. The specific type and brand I use depends on what's right for the particular project at hand. But my first "go-to" is typically from Barb Edwards at GotInterfacing.com. Her interfacing fuses easily, there's just the right amount of adhesive versus fiber (to avoid "burn"), and I like the added body in her products over similar products from other brands. See my handy reference which provides a side-by-side comparison of Barb's products with information such as recommended fusing times, and suggested applications by product.
I use Amann Industrial bonded thread in my Juki 1541 industrial walking foot machine for sewing bags. This link includes the Amann color cards and a thread/needle compatibility chart, along with where I purchase. Also included is a Thread/Needle/Bobbin Compatibility chart. View: Industrial Thread & Needle Compatibility
The scissors to love that get it done!
For cutting fabric I first reach for Kai. The Kai 7000 Pro series are really tops, but on the expensive side. However, for many things the Kai standard 5000 series work just fine. Gingher scissors can be heavy in the hand, but for some tasks they can't be beat, and they will last forever...more than other brands. I get asked often what I use to cut out the eyeglass frames in my Frame It! pattern line. For this I use shorter and very sharp scissor which makes a significant difference in terms of maneuvering the curves with greater precision. (See small 6-inch large handle Kai N5626.) For Cutting out paper pieces, I use Tim Holtz Tonic 9.5" and 7" Titanium Kush-Handle micro-serrated/non-stick scissors.) See full PDF for images of my top choices and where to shop for them. PDF: Go-To-Scissors