Bellend
If you are serious about getting into GPS then I suggest you check out the following site:
www.cockpitgps.com/
If you download a copy of the Cockpit GPS PDF file you will find it is well worth the voluntary $10 payment (in fact it's worth $100 in my opinion!).
As soon as you have mastered the basics of a moving map GPS then you won't look back. However, if you take a half hearted approach and don't bother to learn much more than how to operate the 'direct to' function then you're looking for trouble.
Just like using dead reckoning with map and watch, you really need to complete your flight planning on the ground to get the most out of it. In order to do this quickly and safely you need to understand the kit. Cockpit GPS is a great starting point.