If you're planning to ship via a courier like DHL or UPS, the easiest way would be to call them - they can provide an exact quotation through the phone. But there is some info you need on hand before you call :
You'll need to pack your flight case inside a cardboard box (using newspapers, bubble wrap, Styrofoam peanuts etc. as cushioning). DHL etc. would need the dimensions of that cardboard box (to calculate volumetric weight) and the postal code at the destination country. You'll also need to indicate if you or the recipient is paying any import taxes that may be incurred upon receipt. Some paperwork you'll have to fill up but they will let you know what you need to do when they collect the package.
In general you can expect to pay about S$400-500.
I have shipped some guitars to the US before. Hope this helps.
