no worries buddy. It's an extra 29.99 for the unlimited data plan i believe. I'm not sure if you can get less than unlimited for less cost per month but when you have some free time just go over to a verizon store and ask them. usually there's at least one chill guy around who will understand that not everybody can drop a ton of money but still could benefit from the uses of a blackberry.
But I will say that if you only want one because it's cool and a lot of people seem to have them these days, wait till you're out of school or until you really need it. I didn't get one until I graduated and started my job and I definitely make full use of it now.