Best Buy: Headset Buddy Phone Headset to RJ9/RJ10/RJ22 Headset Plug Adapter 01-PH25-RJ9
Amazon.com: BuddyPhones Explore+, Volume-Limiting Kids Headphones, Foldable and Durable, Built-in Audio Sharing Cable with in-Line Mic, Best for Kindle, iPad, iPhone and Android Devices, Sun Yellow : Electronics