DOTA 2 is currently in beta testing. When the game is released, this site will collect, analyze, and report DOTA 2 Item pricing for the community at large.
Access our API-driven Dota2 In-Game item list and Dota2 backpack viewer
By popular demand, we are currently compiling prices based on beta item trading. We hope to release a preliminary spreadsheet soon. In the meantime, please feel free to contact us at our new subreddit: http://www.reddit.com/r/dota2spreadsheet.