Domestic Shipping Rates for media mail are $3.50 for first book and $1 for each extra. Priority Mail is $9 for first book and $1 for each extra.
International Shipping Rates are $15 for first book + $3 for each additional. This includes UK, Europe, Japan, Austrialia, South America, Etc.
Canada is: $12 for first book and $1.50 for each extra book