Because international postage is so expensive, my policy is to charge my international customers exactly what the Post Office charges - I do not make a profit on postage or add a handling charge. 

For shipments within the U.S. I also offer shipping via UPS which is now significantly less than Priority Mail for heavier packages - and it includes real-time online tracking and insurance, making it a real bargain for expedited shipments.

If you choose Media Mail, PLEASE be aware that it can be very slow.  I ship all books within 24 hours of receipt of payment (excluding weekends and holidays) but the Post Office sometimes takes several weeks to deliver Media Mail. I have had Media Mail packages take over 5 weeks to reach Alaska and Hawaii.