I use the RYA's Electronic Chart Plotter (
www.rya.org.uk). It uses Admiralty raster charts and is easy to use. It will interface with a GPS.
I plot waypoints on it and transfer them to my old Garmin 126 (which won't connect to the PC AFAIK). Print out relevant bits of the charts and laminate them to take aboard. You can update the charts and tidal info every year if you want to. I haven't so far, as the rocks round here don't move much and buoys etc. are few and far between.