PS. All these American symbols conclude with the letter "F", indicating they are a Foreign stock on an American Exchange. The Canadian and Australian symbols will differ on their native exchanges.
Also note they are listed as PK (Pink Sheets) or (OTC Over the Counter), because their status as juniors, size of the company, only allows that they be so classified when being listed on American exchanges. It is not a reflection on the viability or quality of the company.
Some brokers like TD Ameritrade allow you to purchase these stocks directly. Others like Scottrade, currently, will purchase these only through their native exchanges, because current low volume on American Exchanges may delay the transaction, for hours or even days if you are buying a larger quantity, and they will charge a broker's fee ($20 for Scottrade) in addition to their normal trading fee. You may have to call your broker to make these trades.
Check with your broker, or ask about this if you are setting up and account.

Best of Luck.