i use http://www.johnsonstelemetry.com/
for their collars and i use a wildlife box http://www.wildlifematerials.com/
I use these on bear hounds and iam not sure of what type of application your looking but these work exceptionally well for me.
there are others that you may find easily on most search engines, magnum telemetry, quicktrack,and, wick outdoor works carries a line of tracking collars as well.Hope that helps you out!
Jim Zumbo, Craig Boddington, Ron Spomer and Wayne Van Zwoll are all solid contributers to the modern hunting literature. Through their gifts (both hunting and writing) they make us better hunters. Whether it is letting us learn from their mistakes or by teaching us new techniques,they help us harvest more game. But I suggest looking to the oldies, the fathers of the outdoor writing craft, to learn tricks that you might have not used.
I chose to shoot the 270 winchester because I grew up...