Hi, I have a 9 month old but unfortunately I'm about to actually relocate to the states.  I'm in the same position as very nervous about leaving here and not knowing anyone there!    I also have a 3 1/2 year old and I loved The Albrighton centre.  Used to go to loads of groups there, some free some like ?2.  Lots of mums there to meet.  http://www.albrightoncommunitycentre.org/whats-on/    Dulwich Library on a Wednesday for baby sing a long, they also do baby toddler group on a thursday.    Dog Kennel Hill school do a great messy play.    Another great website is http://www.edtots.co.uk/    Good luck