Here is a resource site for those interested in market research. There's lots of good content and tools available here. This link comes courtesy of Marcus Zillman's excellent blog.
The Marketer's Portal is a good research tool, a clearing house or hub for online marketing resources. They claim links to over 5,000 sites along with live news feeds. It's a good starting point for building your personal collection of marketing resources.
Qualitative vs. quantitative marketing research. What works best? Here's a good article from the Wharton school on some recent trends in the field of marketing research. I was particularly struck by the use of brand communities as this ties to research I have conducted on this type of customer group.
This is a good article that focuses on the risks inherent in quantitative analysis. Marketers often rely on statistics to make decisions and to justify strategies to senior management. Beware of the potential pitfalls that this author refers to as numbers fetishism. Risks of Quantitative Studies (Jakob Nielsen's Alertbox)