McKinsey & CompanyŠ provide a vast array of good quality basic materials on strategy and many aspects of business design on their McKinsey Quarterly site
John Hagel brings particular insight to structuring businesses and business propositions in an increasingly networked world
Mehrdad Baghai and David White do an excellent job of laying out the capabilities required to grow a business (Baghai, M., S. Coley, and D. White, The alchemy of growth : practical insights for building the enduring enterprise. 1999, Reading, Mass.: Perseus Books. xv, 250.)
Mike Vitale and Peter Weill explore how the ability to decouple chunks of your business system is creating to business model - and hence strategic - options. (Weill, P. and M.R. Vitale, Place to space : migrating to ebusiness models. 2001, Boston, Mass.: Harvard Business School Press. xvi, 372.)
... and more to come