Hi...I also have a 2 year old son and live in Mt. Lebanon. I was looking into daycare about a year ago as I was considering going back to work....here are some ideas...hope they help:
ABC's for Children ###-###-####
I know of some folks who use this daycare and they love it. I have only heard wonderful things about it here...
Marian Manor ###-###-####
It may sound strange, but this elderly facility also has a wonderful daycare. It is highly recommended in the area.
Kids & Us ###-###-####
I was considering this place as it was slightly less expensive -did not care for it for the infant room but it seemed nice for the kids 2 and older. The owner is very nice and I felt very comfortable with her and the staff. They have two locations -one by Virginia Manor and the other by the Bourse Shopping Center (closer to Scott -past the Giant Eagle on Cochran)
If you have any ?'s just let me know...I've lived in Pgh my entire life :)
(this end of town too)