Wirelessly posted (8800: BlackBerry8800/4.2.1 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/102)
Welcome to the BBForums.
Your BlackBerry is not just another cellphone, as you are learning. You will need a BlackBerry Data Plan to get push email, full internet and data usage. Otherwise your BlackBerry will be crippled to many applications.
Check the FAQ "What do I need a Data Plan for?"
http://www.blackberryfaq.com/index.php/Main_Page
Good luck.