High altitude balloon projects have become increasingly popular with students and hobbyists in the past few years. Usually such balloon adventurers would gather up the necessary info and materials from a variety of sources. Now there are sites that offer complete kits. For example, the project in the previous post used hardware from High Altitude Science. That site offers weather ballooning kits and offers on line tutorials.

Here are some similar stores:

• Affordable Near Space Platforms
• Project Aether
• Project Based Learning STEM – StratoStar

Here are a couple of tutorial/testimonials :

• High Altitude Balloon Launch – SparkFun Electronics
• Flight 2 – High ALtitude Object
• Do-It-Yourself Gadgets: Weather Balloon Kit – tutorial (in English) for flying in Germany

Find lots more info and links in the HobbySpace Near Space section.