I bought a G-Scale train set for Christmas from the states. I chucked away the 110 volt transformer which couldn't be used in Europe and I found a spare one in my collection. Take note to see if the model controller requires AC or DC to run and find the equivalent transformer locally.
I'm in France and sometimes I pay import duties and VAT. It depends on the courier service charged to bring it overseas. If you make sure they ship it USPS then there is less chance to pay import duties. Fedex and UPS nearly always charge.