VoIP provider Skype today announced its first foray into advertising, launching ads that will appear in the “Home” tab of Skype for Windows starting this week.

Skype has partnered with companies such as Meebo in the U.S., Ad2One in the U.K., and Ströer Interactive in Germany to sell advertising for Skype in each of their respective markets.

Skype recorded 145 million average monthly connected users for the fourth quarter of 2010 and 29 million concurrent users at peak times. The first advertisers to sign up with Skype include Groupon, Nokia, Universal Pictures and Visa.

“We’re really pleased by the initial response among advertisers. We believe advertising on Skype helps fill a creative gap by giving brands a platform that has broad reach and global engagement, while also supporting large-format, rich and interactive ads,” said Doug Bewsher, chief marketing officer for Skype, in a statement.

Skype “Home” provides a sponsored large masthead space at 650 x 170 pixels, expandable to 650 x 340 pixels, for advertisers to display ads that can include audio or video. Since the ads are on Skype, advertisers can add a Click & Call button in the ad as another call to action. Users also can share an ad to their Facebook or Twitter accounts or close the ad with the “Close Ad” button.