Pics of the tent... Or link to tutorial
There are plenty of ways to make light tent. For structure, you can use Cardboard, PVC, Wood, Steel wire and etc. For backdrop you can use either card sheet or cloth but it shouldn't be glossy. Lighting can either be diffused from outside or directly focused on the object.
I have made a quick search for you and found some nice and easy to make light tents.
DIY light tents made using PVC:
DIY: Building a Light Tent – CW McDonald Photograph
How to make a light tent (DUW)
Photozoid: How to make your own high quality light ten
My Camera World: Mini Home Photography Studi
DIY light tents made using Cardboard:
Dirt Cheap Light Tent | ABieneman's Blo
Light tents with different size are also available for purchase. For example: