The official website for Pokémon HeartGold and SoulSilver opened yesterday at http://www.pokemongoldsilver.com/. The site is currently small, with a full site coming soon. The first screenshots of the English Pokéwalker can also be seen.
The background used for the site features artwork of Ecruteak City by Midori Harada, as was used on the Japanese official site. The country-specific sites available at the time are for the United States and Canada, with region options for Latin America, Belgium, French Canada, Germany, Spain, France, Italy, The Netherlands, Portugal, and the United Kingdom (with Ireland) yet to come.