Good sites for UK EFL job opportunities:

http://www.elgazette.com/ good for UK jobs

http://www.tefl.com/ plenty of UK jobs

www.edufind.com/ good listing for jobs and UK schools

http://www.tefl.net/ good for resources, some jobs

Other Useful EFL sites:
http://www.jobunlimited.co.uk/ Job search engine, not TEFL specific

www.eslcafe.com/joblist TEFL jobs, mainly other countries

www.jobs.guardian.co.uk/browse/education/tefl/index.jsp? TEFL section, some TEFL jobs

Some English schools that turned up on searches:
www.sels.co.uk

www.anglo-continental.com

www.isisgroup.co.uk

www.plus-ed.com

www.staffordhouse.co.uk

www.discoverysummer.co.uk

www.pilgrims.co.uk

www.bell-centres.com

www.newschool.co.uk

www.kingsschool.uk.com