Ok guys, ask and you shall recieve. I made another bag today and I photographed it so I could make a tutorial. Here you go:
This bag is made from some blue corduroy I salvaged off an old pair of pants.
These are the pieces you need to make the bag:

Plus you will need two more smaller rectangles which will come in later. I make my bags between 12 and 18 inches wide, and as deep as I feel like. Also, you can make the straps out of anything long and skinny.
Step 1: Hem the edges of the straps however you like. I folded mine in half, turned under the raw edges, and sewed up both sides.
Step 2: Pin pleats into the area between the two slits. To do mine, I found the middle of the fabric, marked every 1/2 inch out from the center, lined up the marks and pinned. Then sew across the top of the pinned area to secure the pleats.
After Step 2 it will look like this:

And there you can also see the rectangular pieces you will need next. They will need to be as long as the pleated area is wide (length A in the photo).
Step 3: With right sides together, sew the rectangle to the pleated area. Make sure you sew BELOW the seam where you secured the pleats so that line doesn't show on the front of your bag. After you've done that, you will have something that looks like this:

You can see that I've shown the flap you just sewed on hanging down and folded up.
Step 4: Fold the flap up and behind the pleats. Fold the raw edge under and pin back of flap to the back of the pleated area. Sew through all layers from the front, securing the flap over the pleats on both sides. After this step, it will look like this:

(so sorry the photo is really really blurry, but you can see that it looks almost the same on both sides, one is just the inside and one is the outside of the bag)
Step 5: Sew together the flap you just made and the tab on the side of the body pieces, going down to the end of the slit you cut in the body pieces. Refer to arrow 1 in the picture above. It will look like this from the inside:

Step 6: With right sides together and using zig-zag stitch, sew around the outside of the body pieces of the bag. Turn right-side out. If you haven't pressed anything yet, you may want to press the bag now

. It should look like this:

Step 7: Fold down the top edges that are sticking up so they are level all the way around and pin down. Pin the straps right inside the edges of the tabs that you just folded down. Here's a close-up on what it looks like pinned:

Step 8: Sew all the way around the top of the bag, securing the straps and giving a nice edge to the top of the bag. Voila, you are done!!
Here's what it should look like when you finish:


The finished dimensions of this bag were 15" wide at the widest point by 8 inches tall. The straps were about 18" long, so they are 9" tall when on the bag.
If you guys have any questions please let me know! And if you come up with any tips or tricks, I am pretty much a novice so I would love to hear them!