I'm sure you'll get lots of replies saying that avoiding oppressively-made goods is just cutting off your nose to spite your face, but you're right - and it is possible. Unfortunately it's difficult to live in the UK and avoid it 100% of the time, but it is possible to get 99% of the way there.
To all those who get a new phone every year, replace their laptop every year, or buy cheap clothes: there is blood on your hands. You don't like me saying it, because it's true.
You *can* get fair trade, sweatshop-free clothes, for example - socks, pants, trousers, shirts, shoes - there's lots of choice and the prices aren't extortionate. You might think that not getting the latest smartphone won't make the tiniest difference to Apple or HTC, but what it means is that you're not contributing to slavery.
Unfortunately, it's not so easy when it comes to electronics - nearly everything is made in China (though my monitor was made in Europe - no doubt the components came from somewhere horrid). But this can be minimised this by buying less, not falling into the constant upgrade trap, and not thinking of electronics as disposable consumables.
Finally, Matt Assay: Fairtrade chocolate is available everywhere - are you going out of your way to buy the slave stuff?!