It looks like Google is preparing to make a push for serious growth in Russia — the search giant announced today that it’s acquiring ZAO Begun, a Russian contextual advertising service, for $140 million.

Begun is currently owned by Rambler Media, one of the largest Internet portals in Russia. The deal gives Google a real foothold in the Russian market, connecting it to a larger network of both advertisers and publishers.

Google’s press release points out that digital advertising is experiencing rapid growth in Russia. A recent Mindshare Interaction report found that Russia’s total Internet advertising market doubled to $367 million 2007, with contextual and search advertising accounting for $210 million, according to Yakov Sadchikov of the search company Quintura. Google only accounted for $10 million of that amount.