Are irons always only sold in sets?

I went to Dicks yesterday to see a store with a large selection of golf gear and it was pretty cool.  I noticed that you can buy almost every club separately except for irons, which only seem to come in sets (unless I missed something).  Is there a reason for this?  If you wanted to change a specific iron, you would have to purchase an entire set?

When one buys irons, one [i]typically[/i] buys a set. Now, the definition of "set" is a changing a little, with fewer and fewer people carrying even a 4-iron anymore (that's another story for another time). But most sets are sold 4-PW+AW (8 clubs total), and many people will buy all eight, even if they're leaving two or three of the clubs out for one reason or another. Now, that doesn't mean you have to buy it that way. For example, a few years ago, I wanted a Nike VR Blade pitching wedge. I didn't want to change my other irons, and I didn't want to spend for the set. But I asked my local store to order JUST the PW in my specs (length, lie, shaft, etc). It cost me 1/8 the cost of the set. It's rare for someone to go to a store to get an individual iron, so they don't have a display of separate irons.

You can custom order individual irons. The individual components of an iron set are not likely to be big sellers at the retail level, and where they are sought after, they're sometimes available.

As stated by other, you generally have to order them. Other than that, the only time I have seen individual irons sold at a retailer, they were last years model and were demo clubs.

Most people buy irons as a set but you can sometimes find individual irons on Ebay.  They arent exactly cheap, especially for newer irons but they can be found.

Most companies sell seperates. Ping does. Wilson does. I just ordered a 3iron. When I bought my PING's a few years ago, i bought them 3 at a time. Mizuno sells single Irons. As does Nike and Titleist. I would say they all do, just find a pro shop that sells what you want. Big box stores may not be able to, but I would say they can.

^ Pretty much. I think it's a great way to go. If you're a 13 handicap you could get Titleist AP2s for your 7-PW and 3-6 AP1s. That gives you forgiveness in the less lofted clubs and more feel in the shorter ones. Just an example.