How can I buy an abandoned home?

Are you trying to find out who owns it?
You would have to go to the court house and check with the recorder of deeds and the property tax office to get the name of who owns it.
There is a way to look it up on the internet by going to the county court house site but I haven't done it in a while so I forget the steps to get to it.

All houses and property is owned by someone, you have to find the perosn, company or government that owns it, and make them a offer.

You can go to the dept that registers deeds and find who is on the deed, next you go to the property tax department and see who is being billed at what address on the property. Checking the deed also shows if there is any liens on the property.