google navigation manual or tutorial?

[cornstarch]

is there a manual or tutorial available anywhere for google navigation - i can get it to work [and it works quite well] but there appear to be some fairly interesting options that i can only understand by trial and error - and there are other features that may or may not exist - for instance, it's not clear whether there is anyplace to store a home location [other than in the list of already used locations] that can be used as either the 'start' or 'end' point for navigation