For the free text messages, you can do it...if you know the SIM's "sub
id" and to get that you must have the IP icon on the ready screen.  If
you do not have it, just call CS and tell them to add basic NOL, get the
"sub id" and later call to cancel NOL.  You will find the "sub id" in
Menu / Net / Nextel.com / Sub ID.  From there you can go to
www.tekniwap.com and follow the steps for "send your cell phone a net
alert".  Thats all you need for free text and NOL service.

As far as the GPS you can use it anytime you wish, but for tracking you
will need Nextel's online services to be able to transmit the GPS data
to another device for useful mapping and what-not.  I don't seen
anything on the website about this phone for ringtones or wallpaper so
can't help ya there.