Google Docs now supports importing scanned documents and then allowing you to edit the converted docs.
How to access what’s new:
In Google Docs, on the upload page, check the “Convert text from PDF or image files to Google Docs documents”, upload your scanned images (JPEG, GIF, PNG) or PDFs, and Google Docs will extract text and formatting from the scans. You can then edit the converted document.
For more information: