While traveling overseas there are a variety of ways to stay in touch with home:
Internet
As a backpacker you will get to know internet cafés very well. These are not very common in the US but are just about ubiquitous in the rest of the world. Internet cafés charge you to use a computer with a broadband connection at some nominal rate (usually US$3-6 hour). This is the best and cheapest way to stay in touch with people at home and with friends you meet on the road. If you don't have a free Hotmail or Yahoo account you should sign-up for one before departing. If you are a college student you may be able to access your university email account through the free, web-based service Campusi.com.
Internet cafés are often close to hostels and if they are not, the hostel itself very often will have a couple computers with and Internet connection available. The internet is also a good way to reserve rooms in the next city at hostels or to book flights with airlines.
Leave some space in your journal for the email addresses for people you meet when you travel. The standard way for backpackers to stay in touch is by exchanging email addresses, and it is amazing how many you can collect while traveling.
Calling Cards
The best way to phone home is to buy calling cards at a local store or hostel. These are sold in set currency amounts like $5, $10, or $20. Note that there are two "flavors" of calling cards found in most parts of the world.
One type of card is where you dial a toll-free phone number and then a long string of numbers, then the phone number you are calling. The advantage of these cards are they can be used on any phone (pay phone or private residence) while the disadvantage is the hassle of trying to dial in all those numbers without making any mistakes (which can be quite troublesome when you are talking about 30+ numbers!) and you can't tell how much time you have left on your card until you get cut off.
The other type of calling card is the "smart card" (they have a small micro-chip in them) where all you have to do is stick the card in the phone and then dial the phone number you are trying to reach. The advantage of these are they are far easier to use and you can see exactly how much time you have left (by a display on the phone) but the disadvantage of these are they only work on special types of payphones that accept these cards. They do not work on private phone lines.
Most stores will offer both these cards side by side so be aware of how you are going to use them. Also, there are often many companies that offer cards and it can be hard to perceive which one has the best deal. Some may advertise very low rates for a country (like "7 cents a minute for USA!!) but they don't advertise the fact they charge 'connection fees' like $2-3 every time you use the card., which will quickly eat up the amount on your card. The best way is to ask other backpackers or the hostel staff for the best cards.
Unless it is an emergency, don't call home collect or with a credit card. The rates on these calls are extraordinarily high. The last time I used a credit card to call the US from New Zealand I got charged $43 for a 12-minute call!
Postcards and handwritten letters are a still a great way to stay in touch with friends and family even in this email age. They also serve as permanent records of your adventure. A little secret is to buy "airmail" (or "par avion") stamps for your letters which cost only a little more but it gets your mail home in a week or two, rather than the 4-8 weeks it takes by boat with standard postage.
