I started with sony rebranded sat nav I bought from maplin in 2002. It comes with a gps receiver and a software that you can run on a laptop or pc. The gps took like a few minutes to get a lock on and I remember getting lost a few times in my scandinavian trip
Then move on to tomtom using my pda, then tomtom again for my mobile phones. Tried various software and I always find tomtom have the best UI of the bunch. They were good back then but the latest tomtom seems to be rushed. I mainly use sygic drive now and google map for the latest updates or street view which is very useful when finding my destination on a long stretch of road.
I love satnav, some people really hate them though.