In the past, i have become aware of several walking groups around leicester, but i like to walk alone or with close friends, so never joined in.
I think part of the problem is that walking groups tend to be more local groups. 'East Midlands' is far to broad to find anything. The Groups i was aware of were set up in smaller communities. i seem to recall 'Oadby and Wigston Ramblers' for example. As a result of this, they only advertise locally.
It has given me an idea for a website though, since i was unable to find any online directory or resource for walking groups.