Burt,
You posted your message using a computer and an Internet connection, and it should not come as a surprise to discover you need the same facilities when away from home.
Computer: This could be anything from a web-enabled mobile phone (such as a Nokia N series); through the commonly used laptop with WiFi; to dedicated portable computers that run on car or caravan batteries.
Internet Connection: The mobile phone could provide both the display screen and the connection to the Internet, or a pay-per-use connection for a laptop or other computer.
Apart from that, there are many WiFi services that allow you to connect your laptop; some caravan sites offer WiFi (pay-per-use), some town-centres offer WiFi (sometimes free), some coffee shops or similar places offer free WiFi if you buy a coffee, or if you are a BT Openworld customer you receive 4 hours of free WiFi Internet each month, and many other possibilities too.
What's best for you?
Depends what you've already got, and what you want to do - a Nokia N90 mobile phone will let you browse the Internet and answer e-mail - a laptop and 3G mobile phone card will let you do the same - as would a laptop and a WiFi connection in a coffee shop.
Very much a case of pay your money and take your choice - and how much you pay depends on what hardware and contracts you already have...
Robert