I'm new at this, and I have an ETREX30 and would like to know where I can find GPX waypoints of trails in California. I don't care if they are free or paid sites, but I'm looking for a pretty comprehensive library. Does anyone know where I might find something like this?

Caltopo.com is great for trip planning. You can create waypoints using the available maps and then export to gpx. ArcGis explorer is another free program you can downlaod and use to create waypoints. You can do the same with google earth. There is redtrails.com, though you dont know if the information is accurate.

If you actually want to load the GPS full of waypoints that someone else has logged, I can't help as that's not how I do trip planning. But in case you're not aware, you can get a free basemap that should have most trails (although not in route/track/waypoint form) here: http://www.gpsfiledepot.com/maps/view/28.

I didn't know that you could create waypoints with caltopo. How does that work exactly? I tried right-click, but that offers only measuremnts.

1) Log in (from the home page, or under Account on the left bar of the map viewer)
2) Click "New Map" under account
3) Enter a name and click "Create Map"

Then you can draw lines and waypoints on the map and save them as a .GPX file or send them directly to a Garmin GPS using a browser plugin that Garmin makes.

I realize this is a little backwards for most people, and that it makes more sense to be able to start drawing on the map and then choose to save it. Fixing that is on my to-do list, but there are some other features I'm trying to get done first.

Oh, ok. I didn't know that you had to log-in for that.

Awesome work BTW, thanks.