I don't think they are the PB ones I've linked below, based on the distance between the foot rest and the side rails. But they do look similar. If you like them you can always try a PB outlet, give them a call and see what they have. I see these there whenever I stop by.

Overstock has a bunch of different ones. I searched for "saddle stools".
http://www.overstock.com/search?keywords=saddle+seat+bar+stools&SearchType=Header

Here is a link that might be useful: PB's saddle stools

Target has them too!

http://www.target.com/s?searchTerm=saddle+stools&category=0:All:matchallany:all+categories

Here is a link that might be useful: Target Saddle Stools

I am pretty sure those are Pottery Barn. I have seen those in the stores before.

I would definitely sit in one before you buy. I was enamored with these type of stools before I actually sat in one. The front edge is actually quite uncomfortable.

I got those about 8 to 10 years ago from Pottery Barn. I also did not want swivel stools or stools with backs because my kids will 'swivel' the back of the stool into the countertop causing damage to either the stool or the counter. Gotta love those boys!

I wanted 'temporary stools' because they were cheap and here we are nearly a decade later still using them.

My DH is 6'2" and we have used them for years without issues. Adults don't linger on the stools that long. We eat and move on. Every now and then, I sit and read on the stool and they have not bothered me. My kids tend to do their homework on the stool and they have not complained.

It's a pretty common style (and I don't mean that in a bad way) originally imported from China that is carried by several companies these days. I bought ours from a dealer/importer at the Scott Antique market in Atlanta. They're in the kitchen of our garage apartment, and they're fairly comfortable but not overwhelmingly so.
If you want a REALLY comfortable stool with no back, get the stool below from Thomas Moser. Most comfortable stool I have ever sat in - and that is what everyone who sits in it says. Bar none. Not inexpensive, but worth every penny. We have them in the kitchen of our main residence as well as our vacation home.
BTW, I have no affiliation with Thomas Moser - but they should pay me a commission because so many of our friends have bought these stools after sitting in ours.

Here is a link that might be useful: Thomas Moser stools

Addendum: just noticed whose question I responded to, and I believe you're in Athens, GA - correct? (I'm in Atlanta, at least most of the time.) If you're in Athens and you want to actually sit on these stools to try them out, go to the next Scott Antique Market (2nd weekend of the month, Atlanta Expo, Jonesboro Rd. off I-285). The dealer I bought from is outside the front of the South Bldg.
If you've never been to Scott's before, you're in for a treat.

Another comfortable but $$$ is this one from Room and Board.

http://www.roomandboard.com/rnb/product/detail.do?productGroup=6383&catalog=room&category=rm_dining_spaces&subcategory=din_stool

Here is a link that might be useful: Room and Board stool

I don't know about those bar stools, but I can tell you we have very comfortable stools that are similar to a saddle seat but much wider and more comfortable. They are called Cabinfever sawhorse counter stool by Liberty Furniture. They are also not expensive - we ordered them locally and paid around $70 per stool plus $25 each to have them painted black and slightly distressed by our cabinet maker.
We also did not want a back on our stools and found these to be the most comfortable option. We ordered many different stools from different places and found it is important to consider the height of the bottom rung where you rest your feet. This height is perfect. The seat top is 14x18" and comfortable to sit on and linger. We also have a couple extra saddle seat stools in storage that we bring out when we need more storage - so we definitely notice how much smaller that seat is - 9x18"
The picture I'm linking has the sawhorse stool at the counter and it slides under nicely.

Here is a link that might be useful:

Thank you for all of the leads! Yes, nclakehouse - I am in Athens but grew up in Atlanta so I am very familiar with Scott's. Comfort is a concern for sure. It is funny about the tractor stools - my grandparents had several of those in their house (not the Thomas Moser ones but good old Indiana cherry;) and they are comfy ;)

There is one by Baker that I like and I found a knock off at the Mart and Mrs. Howards (an Atlanta store) but it is quite narrow and I am afraid it won't be comfy for my husband and my boys as they grow (the oldest is almost bigger than me). . .

...found saddle stools with cushions, if you are interested!!!
they may be more comfortable...

Here is a link that might be useful: Cushioned saddle stools