On the User Map of the Apnea Training Manager, there is currently one freediver from Cambridge, but unfortunately he did not complete yet the subscription (failed entry test), so you cannot contact him. However, you may consider registering yourself - others will be able to locate and contact you:
http://apnea.cz/usermap.html?search=UK&usrMapType=all
Newly I also added the possibility to found teams and am currently adding diverse features that will facilitate running local clubs - right now I am working on a calender that would allow planning training sessions, diving trips, and other club events. So any regular subscribers may found a team, and then all other member (even those with free accounts) may join them a use all team function. Besides the training calender, the database of freediving training exercises and sessions, team forum, there are also other features in work.
If you decide founding a team on the APNEA.cz website, I recommend choosing a name that will attract the attention of local freedivers.