Business and marketing books for a video game developer

I've been running a pretty large mod team for about 2 years.

We all decided that we wish to establish a game development company, and start working on a title for PC. I have begun forging relationships with people that can assist us in accomplishing that goal. Some of these people told me I need to write a feasability study then a buisness plan. I have all the books I need on auctual mmo architecture and game design, now I just need some for the marketing, management and buisness side of things.

Any suggestions?

Some I enjoyed, generally cover startup info for business/marketing/sales with lots of examples:

• E Myth - http://www.amazon.co.uk/-myth-Revisited-Small-Businesses-About/dp/0887307280/ref=sr_1_1?ie=UTF8&qid=1312894126&sr=8-1
• Beermat Entreprenuer - http://www.amazon.co.uk/Beermat-Entrepreneur-Turn-Great-Business/dp/0273720988/ref=sr_1_1?s=books&ie=UTF8&qid=1312894208&sr=1-1
• Art Of The start - http://www.amazon.co.uk/Art-Start-Guy-Kawasaki/dp/1591840562/ref=pd_sim_b_14
• Founders At Work - http://www.amazon.co.uk/Founders-Work-Startups-27-Startups-Problem-Solution/dp/1430210788/ref=pd_sim_b_4

• Definitive Business Plan - http://www.amazon.co.uk/Definitive-Business-Plan-Intelligent-Entrepreneurs/dp/0273710966/ref=sr_1_1?s=books&ie=UTF8&qid=1312894351&sr=1-1