All along the Internet you can find databases full of downloadable vector maps, now with cGPSmapper Shareware you will be able to convert those into the format of your portable GPS to carry them anywhere you need them.
It allows you to create maps, edit them, mark them, and even color them. The program has a very accessible and understandable interface with which you will be able to design or trace your future routes and mark the places you have been.
It supports a wide range of formats such as ESRI and OziExplorer.
Compatible with every Windows OS and waiting for you to try it!