Quite a few people have such ovens here in Colombia. I had one in the 70s in Bolivia. Simple, easy to build with bricks, cement and clay (for the lining). In Bolivia we just built a nice wood fire inside, took out all the coals, slid in the bread, shut the opening, sealing with some wet clay, and...great bread. I'll look closer at the one on my running route later today.
I built one last summer. I've tried to attach photo...
It took us about a month to build it by working a few hours here and there after work.
We spent about $100-150 since We dug up the clay in our yard and found cement blocks and firebricks. If you want more personal info, let me know.
I used the book by Kiko Denzer.
The job is quite labor intensive but fun and totally rewarding. I plan to build another and would help someone else build one too in a heartbeat.
We broke it in with a pizza party and cooked about 50 pizzas. Everybody was really impressed.
There is one in my neighborhood, the immediate neighbors dislike it due to the smoke. At least one of the neighbors had air conditioning installed because when the wood fired oven is in use, they can't leave any windows open.
The chimney is taller than the fence, probably around 10' high, and that is not high enough to not smoke out the down wind neighbor.
Same thing is true of a bbq pit or a grill that is burning wood. A little smoke goes an incredibly long way.
Someone in my neighborhood this winter either rediscovered their fireplace or installed a wood burning stove/furnace. My dog came in one night and I suddenly smelled wood smoke - it was in his fur the way barsmoke clings to your hair/clothes. I quickly ran outside in stocking feet to make sure the other half of my house wasn't on fire (I own a duplex). Finally figured out someone must have a fireplace or stove fired up. It happens once or twice a week now. My feet thawed out.
There was a discussion on this board just after New Years about this. Winter and the loss of the vehicle I used to haul materials puts mine at half finished. The vehicle is back and in a couple months spring will be here so I can finish it. Three approaches, those with too much money buy an Italian insert and hire a contractor to build an outdoor palace around it. Others cobble together a foundation and build a mud based one for a hundred bucks. And then there are those who build with firebrick and refractory concrete for a several hundred dollar one - see The Bread Builders from ovencrafters.