I've recently started using The Missing Sync for Blackberry after months of frustration using the free PocketMac application. Hands down, save yourself from literally days of pain and suffering and just get the Missing Sync for Blackberry. It works with Entourage as well as all of the iApps. I'm using it to sync with iCal and AddressBook now, although I could have it sync with Entourage instead (I'm trying to wean myself off of M$ eventually). The Notes app is also great.

just do it!