You can use all kinds of available maps on your device: street maps (e.g. City Navigator), topographic maps and sea maps (BlueChart). For your device you have to use "image" versions (file name *.img). For trip planning on PC you must use "MapSource" versions, also called CD or DVD version or gmap. If available you should download "unlocked" maps - they are easier to handle for newbies. The actual program for trip planning is
Garmin BaseCamp - free available for Windows and Mac OS.
Here you find all Garmin-Software for Windows
[Please Register or Login to download file] ...and for Mac
[Please Register or Login to download file] These are the basics in a few words. If you have special questions for installation and using of maps or other things, please ask specially.