I buy all my stocks using either NatWest or Abbey (Santander).
You can buy stocks on foreign markets through any broker although you must fill in a form allowing you to trade this way – so allow an extra few days for this to go through the system as the form often has to be posted to your broker rather than done on line.
Just call your broker and tell him you want to trade on the overseas markets. Alternatively there may be a form that you can download from their website. The form you need is called a W-8BEN form.
It is worth getting this set up anyway as it costs nothing and will be in place when you are ready to trade.
Trading on line cots around £15 per trade – less with some firms and once you have set up your account it will monitor your trades automatically for you. Most times you can trade on line but if I buy overseas using Abbey I have to call the dealer as the system cannot find the share price of overseas stocks. If you want to buy on the US or Toronto markets remember they do not open until 1.30 pm our time.