Well you really have two easy options here. First is to use Microsoft's Outlook which will sync with your Blackberry very easily. Second is to use Google's GMAIL Calendar which also has software to sync between it and your Blackberry. These are the best two options at the moment.
I have been using google calender with the Google mobile sync. and it work beautifully. Anything that is included in your gmail calender notes, alarms Location gets transfered to your BB with the sync. After I saw this I threw my dell PDA in a draw....
