Germany
Answering some of your questions... (I'm in germany)
Preferably, it needs to be a country where I can get by with English, since I don't speak any other languages (typical American, I know).
You can get by with english fairly well in the bigger cities, as most people here speak english to some degree, but I suppose it would be extremely helpful to learn german.
It needs to be a country with a high standard of living and a freedom oriented legal system.
As far as I understand what you are looking for, I'd say, yes, we have both a high standard of living and personal freedom (within reasonable limits, basically adults are free to do what pleases them, as long as it doesn't limit others in their personal freedom).
The big difference is, as far as I understand it, that maturity is
assumed and not
enforced.
We also have a pretty good social system here.
Can you own a gun? (not that I do, mind you, I'm just curious)
Not unless you have some sort of legitimation (police or military or for civilians, something like being a registered hunter or in a gun club) and a way of keeping it outside of the hands of those who have not (like children). Guns have to be locked away in a safe, for example. Guns also have to be registered to your person. There are no shops where you can walk in and just buy a gun, like chewing gum or beer.
Judging from the above post, gun ownage seems to be pretty similar here as in the netherlands.
In general, a regular citizen here cannot own a gun, and that is a good thing.
Just look up one of the statistics about people being killed by guns in the US each day, if you want to know why.
What is the income tax like?
Very high (roughly 50% if you have a good income, unless you are married, have children, etc).
I think we have the worst tax system in the whole world... noone fully understands how it works!
Is there mandatory limits on how many hours you can work (like there is in some other European countries).
Not really.
How much does a gallon of gas cost?
Way too much!
Currently € 1.20 per
liter (roughly US$ 5.50 per gallon).
If I run my publishing company from there, what sort of regulations and taxes will I have to deal with?
I'm not entirely sure about that.
Are the people friendly toward Americans?
Mostly, yes. There are always exceptions, but in general people here in germany are friendly and helpful. Being american really doesn't matter much in that context.
Is the government "out of control?"
Not really, but people here aren't very happy with everything they do (especially when it comes to taxes

), but that's pretty normal, I suppose. The next election will almost surely see a change in government (for the better? who knows...), tho. I'd be very surprised, if not.
Also we have more political parties here (basically 2 big and 3 smaller ones, which are of any importance, plus several miniscule ones (among those are some obscure parties like the beerdrinkers or the anarchists, but they don't get a higher than neglectable amount of votes

), that do not even get over the 5% limit which you have to to gain at least some influence) and if you care you can start your own (it's a democracy after all).
Would you consider yourself "free," free to do whatever you want so long as you are not hurting anyone else?
Within reasonable limits, yes.
Restrictions are mostly when your personal freedom limits the personal freedom of others... so there has to be a compromise, obviously.
Anyways, maybe you should plan a very long vacation, where you would live in the countries you are interested in for a couple months to get a picture of your own from your own perspective, which is undoubtedly quite different than ours.
Hope this helps!
Bye
Thanee