I thought I would compile a list of all UK airlines that operate within the UK, most operate over seas but not all.

Air southwest
http://www.airsouthwest.com/

Aircraft Charter Passenger and Cargo
http://www.aviation-consultants.com/

Astraeus
http://www.flystar.com/

Aurigny Air Services
http://www.aurigny.com/

Avianca
http://www.avianca.com/

Blue Islands
http://www.blueislands.com/

BMI British Midland
http://www.flybmi.com/

BMI Baby
http://www.bmibaby.com/

British Airways
http://www.britishairways.com/

Eastern Airways
http://www.easternairways.com/

Easyjet
http://www.easyjet.com/

Fly BE
http://www.flybe.com/

Fly Globe Span
http://www.flyglobespan.com/

HD Air
http://www.hdair.com/

Logan Air
http://www.loganair.co.uk/

Lydd Air
http://www.lyddair.com/

Monarch
http://flights.monarch.co.uk/

Scot Airways
http://www.scotairways.co.uk/

Thomson Fly
http://flights.thomson.co.uk/

Titan Airways
http://www.titan-airways.com/

Virgin Atlantic
http://www.virgin-atlantic.com/