I think these are available to all, from AOPA ASF in the USA about thunderstorms and it gives some pretty good advice, although most is aimed at flying in the USA. Well worth a read....
CBs in the USA tend to be more of a problem than those encountered in the UK, although I agree you have to be careful while flying around any CB.
The ones in the USA develop to a much bigger beast and the danger of extreme turbulance, updrafts, downdrafts and shear are that much greater (not forgetting the hail, rain and lightning!). Flying around them can be difficult due to their size, it's best to land and seek shelter until they have well and truly passed by. You don't often see anvil heads over the UK but in the US they are a regular occurence.