If you can travel there is a new all girls cycling club recently started up in Kent - sevenoaks/tonbridge area http://www.britishcycling.org.uk/web/site/BC/clu/News2008/20081001_kent_velo_girls.asp

Have you tried Hog Hill the new cycling facility near Hainault - to see if there are any others in the same boat, given what the kent girls are doing there seems to be a demaand why not set up your own club.

Try the following (you'll have to Google them for web/contact address):

London Phoenix (mixed club, quite active on the racing scene, I know a few of them live out N and E London way)

Brixton Cycles (SE London but a good club, quite laid back)

For road riding head up to Hog Hill as Daphne suggests or (other side of London...) out to Richmond Park.  You can't move for roadies and triathletes out there at weekends, at least 6 clubs use it regularly, chances are you'll bump into a couple of them whenever you go.  Dulwich Paragon is one of them, very big mixed club, all abilities.  They do regular Sat and Sun rides from Crystal Palace as well.  There's a couple of clubs (road and MTB) based up round Epping Forest way as well which is a lot closer to you but (unhelpfully) I've got no idea who they are!

All the information about Hog Hill can be found here http://www.hoghill.co.uk/ including links to local clubs.

PS the sauna and swimming pool are not present at Hog Hill, the website is a redbridge leisure services site 

Hi Daphne

 I'm in 7 sisters and would be keen to meet up and I have a friend who would probably join. We are both quite novicey though and enjoy a stop for cake somewhere along the way... both mid 20s. Let me know. Easy access out to Middlesex and up round Epping Forest so would be keen to try out some new routes.

Rebecca