You can get bitcoin a wide variety of ways. You can buy bitcoin from individuals that own bitcoin as well as sell them to anyone interested in buying them. The most common ways to acquire and sell bitcoins are through exchanges.
We highly recommend www.BitStamp.net and www.coinbase.com to purchase bitcoins using your bank. Also, you can use www.localbitcoins.com to find people in your area to purchase bitcoin from You can purchase coins from these companies and also sell coins for cash to convert your coins back into your local currency at anytime.
The best way to acquire bitcoin however is to offer your goods or services to others in exchange for bitcoin!