hi, people meet in leeds to train every saturday and are more than willing to help new people out.
the more people in the community the better.
you can check the Parkour Leeds facebook group (http://www.facebook.com/groups/43065963285/
not very active on facebook but everyone there trains in leeds
or the SingleBound Parkour group (http://www.facebook.com/groups/229129357097257/
which is much more active but its spread across the UK
hopefully you find someone to train with/teach you soon