Aberdeen Group
Research and analysis of information technology companies and products. Many free downloads. Custom consulting services.
http://www.aberdeen.com

Forrester Research
Research and analysis information technology companies, products, and services, and of many specific industries. Many free downloads. Free newsletters. Custom research.
http://www.forrester.com/

Gartner Group
Research and analysis of information technology companies, products, and services, and of several industry sectors. Custom research and consulting services. Events and conferences.
http://www.gartner.com

AMR Research Central
Research and analysis of information technology companies, products, and industry trends. Free newsletters.
http://www.amrresearch.com

Meta Group
Research and analysis of information technology products. Organizes events. Custom research and consulting services.
http://www.metagroup.com/

International Data Corporation
Research of information technology companies and markets. Free newsletters. Custom consulting services.
http://www.idc.com

Technology Evaluation Centers, Inc.
Provides information on software vendors and product capabilities. Includes free articles, whitepapers, and RFP sample templates.
http://www.technologyevaluation.com/

Butler Group
Research and analysis of information technology covering products, services, and companies. Organizes events. Some free downloads. Custom consulting services. European and Australian base.
http://www.butlergroup.com/

Ovum
Advising on the commercial impact of technology and market changes in telecoms, software and IT services.
http://www.ovum.com/

Idate
Research and analysis of telecommunications, Internet, and media companies. Organizes events. Free downloads. Custom consulting services.
http://www.idate.org

Robert Frances Group
Analysis of information technology companies and services.
http://www.rfgonline.com

Yankee Group
Research and analysis of information technology companies, products and services, and specific industry sectors. Organizes events.
http://www.yankeegroup.com

Ventana Research
Research and analysis of information technology companies and products. Many free downloads. Custom consulting services.
http://www.ventanaresearch.com

Juniper Research
Research, analysis and reporting of telecommunications technologies, markets and issues. Providers of research reports, consultancy and free white papers.
http://www.juniperresearch.com/

Cambashi Limited
Management and marketing consultancy which focuses on delivering timely services to assist in business growth, market development and profit.
http://www.cambashi.co.uk/