Where can I find regulations in different countries for flight level rules based on direction of flight? I'm from Brazil, and here we use the West/East rule, so we use an odd flight level when we fly between 0/360 - 179, and when we fly between 180 - 359 we fly in an even flight level.

But what should you do in other countries? Where I can find those rules?

I've heard that in Europe it's totally different, and that in some countries in Asia they use meters, instead of feet.

Where can I find this information?
Every country's Civil Aviation Authority issues an Aeronautical Information Publication (AIP) as part of their Aeronautical Information Services (AIS) which contains the information you are looking for. Most likely the information about Flight Level rules will be contained in the GEN (General) or ENR (En-Route) section. For Europe, most information from the AIP's can be found through the European AIS Database