Kashiwagi Shigetaka (柏木重孝) has made a leather hard case sheath for a Daiwa One Touch folding net. Also replacing the original handle with an extending handle. One or both ideas might be of interest if you have a folding net.
In this 1:29 video he demonstrates his creation, hamming it up for the camera.
http://www.youtube.com/watch?v=3VxQvJj4Tus
Tenkarabum sells a similar net made by Shimano, he also shows pictures of the Daiwa One Touch, explaining why he prefers the Shimano folding net.
http://www.tenkarabum.com/shimano-folding-net.html
A few more pictures of Kashiwagi's projects. Not enough informtion to provide how-to instruction.
The leather sheath:
http://happy.ap.teacup.com/applet/ka...1424/trackback
Sheath with extension handle net:
http://happy.ap.teacup.com/applet/ka...1437/trackback
The handle:
http://happy.ap.teacup.com/applet/ka...1436/trackback
I have seen Kashiwagi Shigetaka's style of Tenkara described as hybrid-tenkara. Mostly, I think, because his rods are quite outside the norm. But otherwise his Tenkara gear is very traditional. He makes a lot of different hand crafts; kebari, fly boxes, other creative tool holders, etc. Which he sells through 2 or three different websites. He is an inventive guy who follows his own drumbeat. Here is a bamboo rod cap he has made also posted on his blog.
http://happy.ap.teacup.com/applet/ka...1405/trackback
Beyond these links to his blog he has a couple of other online commercial websites, at one time I had a link to an English language site, but can not find it or it has been taken down.
Anyway, an interesting net sheath idea.
fwiw,
D