This site is about homesteading, not survivalist issues, or, in a way, both. But the focus is homesteading. Radios and communications are imperative on a farm, especially if you own some land. A good unit can offer you the ability to talk to your mate in a field or garden, and some units are made water/weatherproof when a cell phone would whither up and die. Also, the right communication would benefit anyone in an emergency, from channel 9 on a CB, or a short wave unit that will let you reach out and touch a family member half way around the world. Here are some of your options.
CB Radios. CB's are great for short range. They are actually even better for some short range applications because police rarely monitor them anymore, and when they do, it's usually channel 9. For neighbors, and communicating during an emergency to the people close to you, they are great. Generally a CB range is between 1 to 25 miles according to terrain, weather, and vegetation between you and the person you're talking with. The benefit is that you can talk without being overheard, the drawback is that you may be overheard and using the CB for more than local emergencies is useless.
Cell Phones. Cell phones almost always have a 911 feature. Even if you don't have a plan, a pre-paid phone can still get you help. They are great for emergencies assuming that you have cell service, but in a real disaster, the towers could go down and you would still be out of touch. One of the biggest drawbacks is that cells can be traced, and conversations recorded. They may be good for emergencies, and they are excellent for communication in general, but they, in my opinion, are marginal in a real disaster. They may rate an 8, but you need a backup of some sort. Oh, just to note it... police have devices that shut down cell service in an emergency and even though this might not affect a homesteader, it can be disasterous if they are using the blocker when you need help the most.
Short Wave. Short wave, if you have a tower, has a huge range. You can also piggyback an internet line over a shortwave radio. They are open for anyone to hear, but in an emergency, many services broadcast over shortwave. Getting into it's not hard, and not that expensive. A couple of hundred will get you a unit that will let you talk/listen to others, and a few more hundred will get you into a unit that will let you talk to family in Paris or listen in on communications in Iran. During an emergency, a shortwave will connect you to others who still ahve cell service, or home phones, and with a few calls someone can send you help even when you are pretty much offline.
Email. Don't laugh. Even when the phones are out, email is often still working. Your phone may be able to get an email out, and a receiver may still have internet access even if a cell tower is damaged or DHS shuts down communications.
GMRS systems. A GMRS system is a radio that has a range of about one mile. For a small farm, or even a larger one, this may be a viable solution to talking to someone while you are out and about. It's benefits are that a General Mobile Radio Service is limited in range but still sufficient for most home uses, and the biggest drawback is that the FCC licenses them. There is an 85.00 fee (may have changed) for using the radios, but there is a frequency called, FRS or Family Radio Service that does not require licensing. Be aware that the radio will work without paying the fees, and they are as little as 50.00 for a set with the charger and stand on Ebay. For a SHTF scenario, they can be fantastic. Now, I've read that they have a 30 mile radius, but in reality, most people say one or two miles. If you look at Midland, they sell a radio that uses a set of low power channels that are not licensed, as well as the licensed channels. Nice radio, just ordered one. Again, the biggest drawback is that everyone who has one can hear your business.
FMS Radio. Similar to the GMRS system, these are glorified walkie-talkies and have about a half mile range.
49mhz radios. These little guys have a 1/8th mile range, and operate on the same frequency as radio controlled cars.