Paul Kemp seems to have had a number of different publishers, one of them being Cassell, now owned by Orion Books. Have you tried contacting his various publishers for a possible lead on his whereabouts?
Many thanks for the link - that proved most useful. I contacted Orion Books who stated that they could not give out his personal details, understandably, but would pass on my e-mail to him. I have now written to him via Orion. Hopefully, Paul will reply in good time.
Thanks again for the link - it is much appreciated.