Hello omster,

Welcome to the GE Community!

Just to add to Bigga's excellent advice...

KML is simply plain text and objects can be copied and resaved in the client so there's no technical way of, for example, encrypting the data (although that would be a rather nice feature). However, your work will likely be covered by copyright law and you might want to add a notice reminding users of this.

You can't link directly from a linestring but if you hold [CTRL] and click on a path, you'll pop up the description bubble - you could place a link in there.

Cheers,

Simon.