Most child care centres in Sri Lanka are based on the Montessori system of education and there are some especially suited to expats and their needs.
Mostly, child care and babysitters/nannies are easily available and babysitting services are not too expensive. Expect to pay about 300 Rs.
Sri Lankan government does not have any programme for supporting child care with vouchers or subsidies.
For looking out for the best child care facility for your child, suited to your place of residence, work timings, budget, age of your child, special need, etc. you can search available options on the net or better still, visit it first hand.
If that does not work, asking around, on expat forums (EasyExpat's Sri Lanka forum and networks) or at neighbourhood parks, and speaking to other expat parents who are already using a facility, would also help. You would get feedback right there and then. Plus, you could ask and get your other queries answered.
Babysitters are generally employed for temporary or short-term periods. Often, a friend of the family or a relative is employed for an evening to watch over the child at the parents' residence.
Most families find a babysitter by word-of-mouth, letting friends and family know that they need someone. Parents may also try posting online or on bulletin boards at community centres, local grocery stores, or expat hang-outs.
For locating such a service online, a great resource is to post on expat classifieds, like on Easy Expat's babysitter search.
For more frequent child care services, you may consider an au pair. Consult the section on 'Au Pair' under 'Finding a Job.'