There are dutch ovens intended for both indoor and outdoor use. Those used indoors have smooth bottoms with a (normally) rounded cover/lid. Depending upon what you are cooking, they are equally at home on the stove top or in the oven. I have only one of these, intended for use in the oven of our 5th wheel trailer while camping in adverse weather.
The dutch ovens intended for outdoor use are easily recognized by two features. Their bottoms have 3 or 4 “feet” like little iron posts intended to hold them up over burning coals rather than setting right down on top of them, (which would block air flow and quench them quite rapidly). Their lids have a “lip” around the outer edge, designed to keep coals placed on top of them from falling off. These outdoor ovens are now commonly referred to as “Camp Dutch Ovens”.
Dutch ovens can be purchased at flea markets/swap meets, at second hand stores, I even picked up a couple at an Army/Navy Surplus Store. Some of the larger Sporting Goods stores carry them – and they can even be found at Walmart, (along with just about everything else you can think of). They will either come “unseasoned”, or “pre-seasoned”. A ton of information on “seasoning your iron ware” has been made available on the Internet, so I will not address that topic – google is your friend. 🙂
It simply does not cost an arm and a leg to get started cooking with dutch ovens – and a properly seasoned dutch oven will get the job done regardless of source. Properly cared for, rather than wearing out they wear “in” and cooking with them just gets better.
In my (not-so-humble) opinion, the best dutch oven a reasonable amount of money can buy at present will come from Lodge Manufacturing – (Hint, you can save a lot of money by purchasing them elsewhere than that web site unless it is a special or sale item – I use Amazon.com because I have an Amazon “Prime” account and get free 2-day shipping). The “best of the best” has been sold under the name “Lodge Logic” for quite a spell – but the bottom line is that indicates the oven you are buying has been pre-seasoned with their own secret process. I have no idea how they do it – but a pre-seasoned Lodge dutch oven is absolutely ready to go when you received it. Just a minor washing – heat it thoroughly – start cooking. Whatever they are doing, it is simply RIGHT. A pre-seasoned piece of Lodge iron cookware is far superior to anything I have been able to achieve personally – and given that quality it is far easier to KEEP it properly seasoned. Just my opinion, but based upon my own personal experience so it is an “informed opinion”. Having said all of that – not all of my own iron ware is Lodge Logic – I just wish it was. -=dave=-