hi all,
there is an indoor playground in kelmscott called "Activiate". children under 1 are free. there is a ball pit, slide, bikes and other activities for all ages, and cafe for mums.
also, in cannivale, there is a play and learn centre called "monkey bars", which is so good. would recommend it to anyone. you stay there with your child for an hour to hour and half(depending on age of child), and you meet other parents, do arts and crafts with your child. there is story time, letter of the week, nunber of the week, and lots more. can't remember the adress, but google "monkey bars perth"
also in gosnells, is a really good program called "tumble tots", which helps promote physical and social development for your child.
swimming lessons, at local pool (Armadale have one) are also great way to meet other parents, then you could go onto creating your own mother's group. hope this helps.