FTA reception requires three main components: the receiver, the LNBF, and the dish.
The receiver is the brains of the system. Its job is to convert the DVB (direct video broadcasting) signals to something your TV can understand. It can be a standalone box or a card for a computer.
Most modern receivers should be able to handle HD channels. Although there are still a surprising number of standard definition channels available, it's much better to be able to watch both kinds. If you find a really low-cost standard-definition receiver, that's okay; the receiver is the easiest component to upgrade.
The LNBF (low-noise block converter feedhorn) is the piece that points at the dish. The LNBF translates and amplifies the weak signal from the satellite into a stronger signal that can travel to the receiver via RG6 coax cable.
The LNBF's signal sensitivity is measured in decibels. A rating of 0.5 dB is okay, and 0.3 db is good. The lower the rating, the better you can receive weak signals.
Almost all FTA LNBFs use linear polarity. Some are "standard," with one local oscillator (LO) frequency; others are universal, with a range or LO frequencies. In North America, almost all FTA Ku-band channels can be received using either LNBF type.
The dish is the simplest part, although it's the hardest to ship. The minimum diameter is about 75 centimeters (about 29.5 inches), but a larger dish will help you pick up more, fainter signals. A larger dish will also help maintain a viewable signal when it rains. As noted in Part 1, you can install a dish up to one meter wide (about 39.3 inches) almost anywhere in the US.
Check with local satellite dealers for their dish prices, then check the prices of online dealers. Because dishes are so bulky to ship, you may want to buy a larger dish locally. If you're just getting started, your best deal may be a package price for the whole system shipped at once.