Here are some stores that sell (indie) games.
Most of them don’t state publically how much they take but the standard rate is usually about 20-30%.
However don’t forget that you can always sell your game directly with a payment processor.
- Sales Report by developers of Defender’s Quest (Gamasutra)
- Improving Steam Greenlight: Valve Meets Indie Game Developers (Crunching Koalas)
- More Greenlight (Rob Fearon)
- Steam Greenlight Articles (Rock, Paper, Shotgun)
- Edmund McMillen about Steam (Gamasutra)
- Volume Vs Price: One Indie Dev Describes Steam Sales (Ars Technica)
- Market Shares Of Digital Distribution Platforms (Deals4Downloads)
- So you’d like to have your game on Steam? (Steam Official FAQ)
- Improving Chances of getting on Steam (TIGSource Forums)
- Steam Discussion (TIGSource Forums)
- Gameolith (Linux Games)
- Attack of the Indie Steam Clones: IndiePub, IndieCity, Indievania, Desura (NeoGAF)
- EA Origin (only sells EA Games afaik)
Note: This is just a temporary solution (I will make a proper banner for each of them later).
Digital Distribution Platforms (Wikipedia)
Market Shares Of Digital Distribution Platforms (Deals4Downloads)
Which services have you ever used to purchase a PC game? (TIGSource Forums Survey)
Selling Your Game To A Publisher (TIGSource Forums)
Where Can I Sell My Indie PC Game (Gamasutra)
Article about 4 Indie Distribution Platforms (Ratking)
Video Game Publisher (Wikipedia)
List Of Video Game Publishers (Wikipedia)
Game Publisher Contact List (IndieVision)