Like Twinprism, I also grew up on a potato farm. It would indeed help to know when you would like to obtain the potatoes, the size and the purpose.
When I say the purpose, some don't realize that potatoes are graded on a scale and what a "baked potato" in NYC would be, is a very precise size. Conversely, what others may want for a big pan of hash browns doesn't require an exact size.
Since potatoes are usually planted by mid-May and harvested by mid-Oct., from July on different sizes can be freshly dug. Also, it depends on where you are in the state. Along with the Blackfoot resources, the new organic food market in Idaho Falls should carry fresh potatoes plus numerous farms.
It really depends on your purpose, how many would be present (potato harvesting equipment is dangerous and not appropriate for children), if you plan to go to a farm and your timing.
BTW - no two potato farms are the same. What may seem simple is actually quite complex. Progressive farmers go to continuing edu and on-going courses to learn better production of potatoes. Others do things the same way they have for decades.
However you receive them, I hope you find the perfect taters for you!
MSR