HI,
You could try the following site is has loads of links to balloon related sites around the world. Including the sites of all the Round the World balloon attempts.
http://www.provide.net/~pratt/ballooning.htm
Here in the Uk we have the following site the British Balloon and Airship Club also produces a mag called Aerostat. Details can be found at
http://www.bbac.org/links.html
Pre owned balloons and equipment are advertised at
http://vweb1.hiway.co.uk/zebedee/index.html
Have fun
Ian balloon pilot