Surcharge on overseas shipping

I like to keep things pretty simple and have used Per Item Shipping (ie £1.00 per item).
However, that doesn't cover the cost of shipping to overseas customers.
I've tried searching the forums for the past two days but if there is an answer I've missed it.
I do not use dimensions or weight on any of the items I sell. They are all pretty lightwight and £1.00 usually covers postage - except for overseas.

Is there any way to add a charge (on checkout I guess) if the customer is based overseas (not in UK).

You'll need to use two Geo Zones: one for UK and one for Overseas. If you just want flat rate shipping, you can use the weight-based shipping module and use a single high rate (like 999999:1.00) for each Geo Zone.

Unless you're using 1.4.9.5 or 1.4.9.6, the default weight-based shipping module doesn't have an All Zones feature. (This means you have to add every country individually, which takes a lot of time.) However, I released a free version of weight-based shipping here:
http://forum.opencart.com/viewtopic.php?f=119&t=27150

If you want to use other shipping formulas (total-based, quantity-based, etc.) all of my shipping extensions have an All Zones feature. You can view them here:
http://www.getclearthinking.com/shipping-methods

Thanks for the reply. I already had two Geo Zones set up, but I can't use flat rate shipping because most people buy more than one item, which is why I've got it set for Per Item shipping. I don't mind absorbing the cost when people buy two of three items, but if they only buy one item then it simply isn't worth selling a single item to overseas customers. But thanks. I'll have a look at your extentions.