This is an easy to make version of angled front storage bins. It uses dimensional pine lumber for the horizontal pieces, so they are very easy to cut. The sides are made from plywood cut to fit the outline. With that approach, all you need are drywall screws to hold it together. This design also makes it easy to have any width you want.

Sides: 1/2" plywood - hardwood (Luan) or birch would be best, but any kind of plywood will do, maybe even 1/4" would be OK

Shelf back: 1/2" plywood, since that is what we had in the garage, but 1/4" or 1/8" thick would be fine too.

The following pieces are all simply cut to the same length. We used 19" to fit the room, but you can use any length you want.

(5) Shelf bottoms/tops: 1x12 pine
(4) Front edges:1x4 pine
(1) baseboard 1x2 pine

Step 1: Cutting the Sides

With the horizontal shelves being so easy, the tricky part is cutting out the sides. They need to define the shape of the shelves. To do this, I made a full size template to make it easy trace and cut the sides. You could draw this on the computer, but I just used some actual boards to lay out the sides on some poster board (two pieces taped together). I then cut out the shape, and traced and cut two sides from the plywood. I used a sabre saw for cutting them, but other types of saws would work too. You can cut both sides at the same time. If you do, and have preferred sides to the plywood, make sure the faces are both facing in or out since the one side will be flipped over. You can sand the finished product down later.

There is a gap where the front boards meet the bottom ones. I did not worry about it too much, since it's on the underside of the shelves. I note it in the next step, but I did decide to bevel the front pieces a bit with sanding, and with that, the layout of the template changes slightly. You could also try caulking the underside or something - I just wanted to keep things simple to make.

The approximate heights of each of the shelves is:
top shelf: 41"
shelf 2: 21.25"
shelf 1: 11.5"
bottom shelf: 2" - this one rests on top of the 1x2 kick board

Sorry - I did not measure the angle of the front boards - it looks like about 45 degrees from the picture.

Step 2: Horizontal Pieces and Assembly

Since the horizontal pieces are all dimensional 1" (3/4") pine, all you need to do it cut them to length (for us, it was 19"). For the 1x4s, I sanded a bevel on them to make the fit against the drawer bottoms a bit tighter, but this is an optional step. If you do that, make sure to account for it on the template design in the previous step.

Once those pieces are cut, assembly is very simple - I used 1 5/8" drywall screws from the sides into the shelf - no rabbets etc. I used a pilot hole, then painted over the screws, but for a more finished look, you can use a counter sink pilot bit and wood putty to cover the holes. Be careful not to drill too deep - the sides are not very thick, and the screws will sink in a bit naturally anyway.

I added some felt pads on the bottom to make it nice on the wood floors.