IBIS World - a great resource for UK company and industry sector information.
Ebsco Business Source Complete Market Research Reports - selected market research reports
This information is not usually available freely and is limited in what it can provide.
Keynote free executive summaries – covers UK industrial, service and consumer sectors.
Department for International Trade - industry sectors and business opportunities for over 300 countries.
Press releases from market research publishers (Eg. Mintel).
Euromonitor - view the contents listings for the market reports free of charge.
ReportLinker Sources - good starting place to find industry data sources