Floating shelves are so easy to build.

They need a cleat to hold them up.

This is nothing more than a piece of round steel bar welded to a cleat. Cleat gets installed to the wall and the drywall goes around. Then a hole is drilled into the shelve where the cleats are.

The shelf slides over the cleat.

IKEA sells these by the thousands.

I inventroy cleats in my office for when I need to build something custom like a floating shower bench.

Once you learn more about the process of installing them you will not think this is such a hard job.

They sell some right here on Houzz...

Houston Floating Wall Shelves, 24", White · More Info

Check out this link. You might be able to buy the ones you want today.

SHOP HOUZZ: FLOATING SHELVES

thanks John. that is very helpful. Few comments:

1.) I have picked out a veneer that I want to use on the shelf because I want a very particular wood look. This will require applying the veneer, and maybe staining/finishing too.

2.) How sturdy is the cleat? Would you normally mount it into the studs? I'm looking to hold significant weight on these shelves.

3.) For the bar in the second pic, I'll be using the same veneer. In my mind I need a carpenter to build the breakfast bar, kind of like a hollow box.

1) yes it will need staing and finishing as well

2) Depends on how well it's installed and how wide the cleat back is. Also how thick the rod is. If your adding a lot of weight you will want a good 3/4"-1" rod and a cleat maybe 3"x6"

3) I would be using some kind of L bracket and using the weight of the cabinets and stone as an anchor.

Heading out for soccer. I'll dig out my back up cleats.

Make sure your cleats are anchored into the wood and because of the weight you plan on adding you will need to be careful of the drywall compressing. I would keep the shelf about 2.5" thick. Support it with four cleats. Use 3/4" rods. drill 1" holes in the shelf. Fill with Epoxy. Then place and brace a tad out of level. So when the weight is applied it might a hair down.

Hope this helps.

To keep the drywall from compressing I would use a 1/2" solid wood block over the cleat or some kind of wood screw set to the face of the finished drywall. Does that make sense?