I have found no better ebook manager than Calibre.
Calibre is a free and open source e-book library management application developed by users of e-books for users of e-books. It has a cornucopia of features divided into the following main categories:
- Library Management
- E-book conversion
- Syncing to e-book reader devices
- Downloading news from the web and converting it into e-book form
- Comprehensive e-book viewer
- Content server for online access to your book collection
Calibre will create a folder system based on author's names. As for your specific problem with author's names, Calibre can automatically fix most of those errors for you, by matching your book to online sources on the internet. And even if it doesnt, it makes it really easy to fix them yourself.
I highly recommend you give it a shot. This is one of the few free and open source applications that exceed anything in the commercial market.
I like to keep my Calibre library in DropBox. That way I have access to my entire library from any of my computers (Win,Linux, and Mac), as well as the web.