Been too a few different areas of the world.
The US: seems to be more of a bud focused country. particularly in california, they are very particular about what they strain they smoke, and alot of people grow due to the medical marijuana laws. Its got more of a cannibas connesouire culture.
Other drugs, with maybe the exception of cocaine (and natural things like shrooms) are quite frowned apon. ecstacy doesnt have the popularity that it has in Australia (we at leaast used to be the biggest consumers in the world). and meth is considered to be a gutter drug. many people will happily admit to using cocaine, but will give you a filthy look if you ever mention meth.
South America: plenty of people smoke weed, and there seems to be about as much stigma about smoking weed in SA as there is in Australia. Lots of people drink too, and early in the day I found. The interesting one was cocaine. Most south americans hate what cocaine represents (in terms of corruption and violence) and don't use it. though I did notice that many south americians in their 20s did still use it, but wouldnt advertise their use. Many indigenous groups use ayahuasca and san pedro for medicinal/spiritual purposes. the use of these drugs is widely accepted in countries like Peru and Bolivia. you can buy them at markets. enforcement of drug posession is actually pretty lax, but you wouldnt want to end up in jail.
South East Asia: plenty of meth, weed and opium. locals are pretty secretative about drug use, probably due to stigma and the incredibly harsh penalities if caught. meth (or yaba) has a very bad connotations, but is still used for recreation or to help with work. opium is used traditionally. some of the younger, wealthier types in Bangkok have quite liberal views to cocaine and ecstacy. however, the only drug I saw semi-openly used by locals in any of the countries I visited was marijuana.
BTW, from travelling I have realised many young Australians have very liberal views on hard drugs. We had a bit of a stereotype in south america for being drug pigs