Howdy! The best place I've found for reasonable shipping via USPS is
www.compgeeks.com. They're somewhat of a liquidator, so their stock doesn't always consist of the latest and greatest, and changes rapidly. They've always charged me the normal postage rate for Priority mail. For example, I ordered a barebones system a few weeks ago (26lbs), and they charged me $18 shipping.
Now that I think about it, that's the only place that is consistently fair on shipping. I like Newegg, but they really put it to me for shipping. For example, I bought an OEM video card from them, and shipping was $20! The actual postage on the label was $3.90.
What I normally do now is order from a place that offers decent shipping within the US, and have it sent to a family member, then have them mail it on to me. Not the fastest, but it beats paying the outrageous rates.
That's probably not a lot of help to ya, but maybe some of our "truly" international members will come along ond offer more ideas. Best of luck!