You're welcome to come to the 'craft and crepes' event - this tuesday. Details are in the forum under 'events' 'social events'...
There is at least one playgroup/mums group in English in Wollishofen. I don't have the exact details but can ask someone I know who goes to the playgroup. If you are breastfeeding, there is also an active La Leche League group and one of their meetings each month is usually in Kilchberg. That's usually a good place to meet mums of new babies.
There are several other english-speaking mums groups that meet around Zurich - if you are a church person then the International Protestant Church (IPC) has a mother's group called 'moms and tots'. They are a very large church with plenty of families on Sunday morning. There is also a playgroup that meets at the Anglican Church (st Andrews) - I don't think they are 'evangelical' - just a regular playgroup.
Another place to try is the 'Geimeinschaftzentrum' - that's the local 'community centre' - each local government area has one - and they usually have a range of activities for mums - accessability will vary depending on how comfortable you are across the language divide...
I'd love to get a Montessori mums group up and running at my workplace, in Adliswil - but I'm going to be over-stretched for another few months - until around June...
Anyway, the link for the community centre in wollishofen is:
http://www.gz-zh.ch/gz-wollishofen/gz-wollishofen/