ITC’s Market Access Map see - http://www.macmap.org/
This provides information about customs tariffs (including tariff preferences) applied by more than 200 countries and faced by 239 countries and territories. It also covers tariff rate quotas, trade remedies, rules and certificates of origin, bound tariffs of WTO members, non-tariff measures and trade flows to help users prioritize and analyse export markets as well as prepare for market access negotiations. Users can also find ad-valorem equivalents for all non ad-valorem duties and perform aggregations of products and countries as well as simulate tariff reduction scenarios.
See also Reference Resources: Blacklists and Embargoes and Customs & Non-Tariff Barriers
Also see the YouTube presentation of this ITC service.