If you live in the western US, more than 100 miles from a major city, over-the-air TV can be very limited, available only via a weak signal, or entirely unavailable. There, your only choice is satellite.
DBS vs. FTA
The question is, do you want to pay $50 a month to a direct broadcast satellite (DBS) service like DirecTV and Dish, or do you want to be free? DBS providers will give you a large number of channels, but I find 95%+ of my TV viewing is shows available on local broadcast channels anyhow. That leads us to free-to-air (FTA) satellite.
Over in Europe, Asia, Africa, there are a large number of channels broadcast unencrypted. The western US, however, is the absolute ass-end of the world... separated from the rest of the world by the two largest oceans in the world, and, with such a minuscule population density that practically nobody is interested in serving the area. See previous point about TV reception.
Point being, with FTA in North America, there isn't a big selection. As a rule of thumb, as an English speaker with a KU band receiver, you can really only expect to get PBS, news, and shop-at-home channels. Things get more interesting, however, in the C-band... There you have a much larger selection of channels, intended to be picked up by cable companies and the like, and include all the major broadcast networks. Even though just about all growth is in the KU band, it's clear there is still a lot of life left in the C band. I recommend a dual, C/KU LNBF. You really don't even need to worry about noise and gain figures for LNBFs these days, unless you're looking to pick up seriously fringe signals.
PICKING A DISH
The second issue is size. I don't consider a dish a good purchase if you can't take it with you when you move elsewhere. The only way to guarantee your future land-lord/neighborhood association/etc. absolutely can't forbid you from installing a dish is to follow FCC rules and buy one that is no larger than 1 meter in diameter. Fortunately, this isn't 80s technology anymore, and 1 meter is perfect sufficient for C-band reception. Furthermore, you can get just a bit more signal if you go with an offset dish, rather than an old, standard, parabolic dish, as the LNBF is not located where it blocks signal reception. Since you're size-limited, it's better to buy an offset antenna, and get the maximum amount of signal possible. In most cases, there is effectively no price difference.
Analog has nearly gone the way of the dodo. 4DTV/VideoCipherII is popular in North America, and a good option if you want to get all the standard "cable" channels (for a lower price than cable or DBS, but otherwise, there's practically no FTA content, so it's quite safe to skip it. That just leaves one option, the one that has quickly taken over most satellite transmissions, worldwide: DVB-S... For about $40, you can get a nice PCI DVB-S card, and turn any old PC into a TV tuner, or DVR. But, if you're not very technologically competent, there are also $150 "FTA receiver" set-top-boxes that will do the job as well, if less flexibly.
Though I'm really not interested in it myself, I should at least mention that FTA is commonly used as a euphemism for illegally descrambling encrypted satellite TV signals. Now, DirecTV and 4DTV broadcasts are immune, partly because they are proprietary, and relatively few people have interest in. Dish Network, however, uses standard DVB-S equipment, and NagravisionII encryption, which can be decrypted with "softcam" programs that are available. Of course these things are difficult to find, due to the risk of lawsuits under the DMCA, but "softcam" software certainly exists both for computers (Windows and Linux) as well as "unofficial" firmware for damn near all "FTA" receivers. Yes, it is a bit of a shell-game, and no doubt the vast majority of FTA sales are based on this.
To see what satellite signals are freely available to you, visit lyngsat: http://www.lyngsat.com/freetv/United-States.html
Just be sure to take that listing with a grain of salt... Sometimes, that list shows signals available that are actually from satellites on the opposite side of the planet (see: Playboy One).
You'll also need standard equipment like a dish rotator, that is strong enough to hold the weight of the dish, and communicates with the receiver in some standard they both understand, but that's pretty straight forward to check on. Not to mention good quality coax cable, and absolutely no splitters in-line, or else you'll cause some serious damage.
Buy a compass, and mount your dish so it has a perfectly clear view all across the southern horizon... If there's a tree or a building in the way, you've got almost no chance of getting any reception at all. You can mount it to your roof, or to the ground, but either way, make sure your mount can handle hundreds of pounds of force, without the dish shifting even a fraction of a inch, otherwise you'll have picture drop-outs when it's windy. Manage all of that and, barring heavy commercial air traffic, you should get a perfect signal, all the time. The dish is far larger than it needs to be for KU-bands, enough so "rain fade" shouldn't occur in even the worst storms.
Hopefully this was helpful for those of you considering purchasing a satellite dish. If you still have any questions, feel free to ask in the comment section.