I've read a number of vendor-furnished and analyst reports on mid-market CRM products and companies. Information we obtain from Deutsche Banc/Alex Brown, Hurwitz Group www.hurwitz.com and Cutter www.cutter.com has proven particularly useful, as are activities like walking around trade show floors and interviewing vendors.
At Cutter, you will find reports that range from the "CRM Software Buyer's Guide" to the January Cutter IT Journal focused on "Reorganizing IT for E-Business." (I favor Cutter because the organization often focuses on software development issues -- an area of concern to me as CTO for a software product company.) On the trade show front, last week I visited the DCI CRM Expo in Chicago http://www.dci.com/Brochure/crmchi/ and gathered information to informally benchmark my company's product against industry leaders and to gauge emerging trends such as wireless CRM.
There is quite a bit of information out there. Buyers need to understand the problems they are seeking to solve by instituting a new software regimen such as CRM, assess products that appear to address those problems, and then right-size the solutions to their cost, staffing and organizational constraints.