Hi Richard,
You will enter the ArcPad StreetMap registration code in ArcPad the first time you open *.navmap file. The Rhode Island sample is ArcPad StreetMap and can be used when working with tutorial. ArcPad StreetMap registration codes are different from your ArcPad 10 registration code and data vendors available are TomTom (formerly TeleAtlas) and Navteq. Each data vendor has specific registration codes for North America and Europe data sets.
If you do not have a registration number, you can click OK, and continue using ArcPad in evaluation mode. Evaluation mode allows you to use all ArcPad functionality for 20 minutes.
Cheers,
Denise