Its important that you as a buyer understand your own country's rules and regulations about making purchases from another country.  Some countries are very thorough about checking the incoming packages' values and issuing customs fees.  For example, the UK is very strict about their limit of £15!  If your order is more, they charge a percentage plus an "Administrative fee" to cllect it from you!  The EU generously allows up to €150 without duties.  Other counties are very lax about enforcement.  Canada technically requires customs dutues on packages from the US, but rarely actually attempts to collect it from the recipient on packages under $100.  We are required by US law to declare all orders at the net total amount and classified as "merchandise".  We cannot falsify the amount or mark it as "gift".

Here are some external references if you are unsure about what your country requires.

http://www.dutycalculator.com/help_center/Import-duty-and-taxes-explained-in-a-nutshell/ - General information about duties and a caclulator for most countries

http://en.wikipedia.org/wiki/Customs - General information about customs

http://www.hmrc.gov.uk/customs/tax-and-duty.htm - UK specific information

http://www.cbsa-asfc.gc.ca/travel-voyage/dte-acl/est-cal-eng.html - Canada specific information

http://ec.europa.eu/taxation_customs/common/buying_online/buying_goods/within_non_eu_en.htm - EU specific information