(re: Mixed Up Mother Goose)
Depends what version you want, there are four versions I think.
If you want the CD versions you can get new copies of the Deluxe version on eBay for a couple of bucks. I bought the Deluxe version this year off eBay and it works fine on XP.
The AGI and SCI versions are harder to find – your best bet is to try and find them on so called ‘abandonware’ sites or file sharing networks.