So many questions . . . and here is some of my advice . . . some of which has already been repeated, but it bears repeating.
First and foremost . . . take the time to read the articles mentioned . . . and take the time to look back through the various posts here. There is a wealth of information here at hearth.com . . . information to guide you in how to pick your stove, how to build a hearth and well just about any questions you might have about anything . . . even a how to article on the use of ferrets to clean your chimney.
As you mentioned you have a small ranch and are looking for a stove partly for the heat and partly for the ambiance . . . and trust me . . . there is nothing quite like a woodstove for heat and ambiance. But there are some drawbacks . . . namely the mess (messes seem to go hand in hand with heating with woodstoves), need to plan ahead to get a fuel supply (i.e. you can't just call your local propane or oil company and then turn a knob to get instant heat when you want to use the woodstove) and you will need to learn some basic skills (i.e. how to light a fire, how to clean a chimney, how to maintain the stove.)
With your size house you can either get a small woodstove to just heat your immediate area (and for the ambiance) or you could even go bigger and get a stove to heat your home house (and still have the ambiance.)
There are many different makes and models . . . and sizing them correctly for what you want and expect is crucial. You also need to pick out what features you want in a stove -- is simplicity more important than the look of the stove or is the expense less important than its finish for example. In general you have three choices in stoves: steel, cast iron or soapstone. There is a good article that lists out the pros- and cons- of each type . . . basically all of them will meet your needs and all are good . . . some folks are just a little more partial to one type over the others. I would strongly encourage you to get an EPA-compliant stove -- you will be able to get more heat with less wood than a non-EPA stove . . . plus you'll get that warm and fuzzy feeling for being environmentally responsible with a less polluting stove . . . and your neighbors will think that you never, ever use your stove based on the lack of visible smoke coming from your chimney. You will also have to decide whether to go with a catalytic converter woodstove or a woodstove that uses a baffle system with secondary burning . . . for some folks this is a major issue and for other folks it's not a big deal as to which type they get.
Take a look at the various manufacturer websites and peruse through their models . . . and take the time to look at the sizing and length of burn . . . but also be aware that there is no one agency that certifies these times and sizes. Some good advice I was given was to go a little bit bigger when choosing a stove . . . and to be aware that the burn time is typically the most optimistic and may in fact be from when the match is lit until the fire burns out vs. use-able heat.
Insurance: My opinion. Call first. Your insurance rates may or may not go up. Your insurance company may also require you to meet specific requirements . . . such as having the stove and chimney professionally installed or they may require an agent to check the final install. In any cases, my opinion is that it's better to check first than to find yourself hit with a steep increase in a premium after the install is done.
Local agency: Some places require permits and some places do not. Check with your local town, county or state. Here where I work in Bangor you need a permit to put in a woodstove. In Unity where I live (small town) no permit is necessary.
Self Install: Again, a lot depends on the local authority having jurisdiction and the insurance company policy. If you can do a self install a lot of it is simple enough for anyone who has done some basic DIY stuff.
Good luck . . . and welcome to hearth.com.