I managed to get a keyboard (electric piano) from a shop at almost less than half price. Problem is neither my wife and I knows how to play the piano. So I did a search on internet and found many resources to help us to learn how to play the piano. (Just that it may not tell us if the timing is correct).
The following are some good resources:
Free Piano Lessons
Get Piano Lessons
As you learn and want more material, you can then download free music sheets from the following: