A PC power cord - this is a very standardized cord (on the PC end) - If purchased overseas, it will have the "normal" (for that locale) plug-in end and the PC outlet . Most quality PSU's will accept either 110 or 220 input (might have a switch in the back to flip, might not, some newer ones have automatic sensing).
I do not know about printers since I rarely use them.
You can also buy international power adapter kits like this herehttp://www.simaproducts.com/products/product_detail.php?product_id=79
there is a link on that page to check country compatibility - it is available through newegghttp://www.newegg.com/Product/Product.aspx?Item=N82E16882634023
If you're going to travel with a laptop, I would suggest the converters