The scheme is run by the Centre for Excellence in Leadership for managers in colleges, work-based learning and adult education.
The centre was launched in 2003 to improve the quality of leadership in post-16 education. It is run by Lynne Sedgemore, the former principal of Guildford college, and works in partnership with the Learning and Skills Development Agency, Lancaster university, the Open University and Ashridge management training college.
The new team of mentors, whose services are free, includes principals and senior managers recognised as having achieved "considerable success" in their fields, says the CEL.
Peter Ryder, principal of Leeds college of technology, is being helped by Joe West, principal of Barnsley college.
He said: "I have found mentoring by an experienced and respected principal to be invaluable to my new role. The ability to talk the issues through and reflect on them with someone not directly involved has been a great learning experience."
Colleges and other organisations using the service are asked to pay only for the travel expenses of the mentor.
Ms Sedgemore said: "Mentoring is very much part of CEL's strategy to improve the overall standard of leadership. We are delighted that so many experienced practitioners have volunteered to be trained and act as CEL mentors.
"The CEL was set up as part of the Government's Success for All strategy as a way of improving the quality of further education and skills training through improved management."
The CEL has also been attempting to improve the promotion prospects of people from ethnic-minority backgrounds by offering training packages for black and Asian staff who want to become senior managers or principals of colleges.
It wants to see nine ethnic-minority principals in place by 2009, and claimed its latest success with the recent appointment of Sunaina Mann, who became the first Asian woman principal of an FE college.
The target was set by the Learning and Skills Council. Seven are already in place.
Ms Mann said the BLI's support encouraged her to apply for the job, at North East Surrey college of technology.