Here's a few links regarding escrow service for cryptocurrencies:

http://escrowmybits.com

https://bitcointalk.org/index.php?topic=855778.0 has a list of trusted escrow service provided by BitcoinTalk.org members.
The "Big Three" are:

• https://bitcointalk.org/index.php?action=profile;u=133846
• https://bitcointalk.org/index.php?action=profile;u=37522
• https://bitcointalk.org/index.php?action=profile;u=18321