Scottish Police College contains information on police training, including the Accelerated Careers Development Programme.
Police Scotland Graduates go in at the same level as non-graduates. After two years training (at Tulliallan Police College) and on the beat, you can apply for specialist posts (dog handler, traffic, mounted, detective etc) or the leadership development programme for promotion.
Police Service Recruitment - Could you? Police Service careers in England and Wales
Police Now - graduate programme offered by 28 forces plus the Metropolitan Police
UK Police Service Forces List Links to websites of police forces throughout the UK
British Transport Police Recruitment website