After  crashing and spending an hour looking for my uas last week, I've been  doing some research on ways to find it. I came upon Marco Polo. It's a bit  spendy at about $220, and may not be worth it for less  costly units. But, for those of us who have, or are planning on getting,  a more spendy unit, the couple hundred bucks can pay for itself many  times over with one incident. It's radio frequency based, not gps or  cellular, which most are, and can be useless in some areas. Anyway, here's the link. I'm curious if anybody has been using it and their experience with it...

http://eurekaproducts.com/rc-model-tracking-and-recovery/

Not bad, thanks for sharing. I haven't quite heard of this one, Trackimo seems to be another common brand too.

This is one of the three you hear the most about with drone use. Two are the GPS/cell tower ones, The Trackimo and the RF-V16+RF-V18. And this Marco Polo, which is more like (peer-to-peer) no middle man, but it has advantages and disadvantages. Advantage, if the area has no cell service (GPS is a non-issue). Disadvantage, it's range is short compared to the other types because their range is unlimited. The Marco Polo range is 2 miles max, meaning not real world. Here's some info I found on another site,
System Range
Line of sight: up to 2 miles typical
Open terrain, rolling hills with few obstructions: up to .5 – 1 mile
Dense suburban areas: 2,000 ft. typical

Marco Polo is great, get the RC version tuned for drones and planes

I use the Marco Polo..... I fly without cell service 90% of the time. It is an effective Unit