You would also need to subscribe to a DATA plan as well.
They are different depending upon the phone protocols.
So a iPhone plan is different than a Blackberry plan and probably a Windows Mobile plan.
I suspect pricing is the same, but they are set up differently.
Eg: my Telus HSPA Nokia E71 plan was transferred to a Blackberry, same price, but the way they handle email and data is different.
As for China, I get almost weekly mail from China with ebay technology purchases and as long as you shop carefully and know what you are getting, then usually not a problem.
Eg: computer 120MM case fans that our local computer shop sells for $20, I get for $2+shipping or about $7.
Sure I have to wait a couple of weeks, so I stock up in advance.
With the amount of PC's around here (12+), I don't mind keeping a case of fans on hand.