Some one out here to teach me rednet/gps a bit

I am bizzy with learning lua and computercraft but i have a little bit trouble with rednet and gps is there anybody who could teach me something about it in any way, like a written tuturial or a video or something?

Using the forum's search bar can be a wonderful tool to find stuff

I searched "rednet" when inside the tutorials section and found these for you:
http://www.computercraft.info/forums2/index.php?/topic/6830-how-to-send-multiples-variables-in-one-rednet-message/page__hl__rednet__fromsearch__1
http://www.computercraft.info/forums2/index.php?/topic/3088-how-to-guide-gps-global-position-system/page__hl__rednet__fromsearch__1