The information I passed along to you was a quick - VERY quick - internet search.
I don't know of an online repository of those specific documents. You might check with the tax assessor's office of those counties, to see if they have records from that era.
Are you certain he purchased the land? If he was related, he might have received the land as a result of a will. Or, he might have purchased the land from the estate, if the original owner's property was sold at death.
Check the probate records and find the will or estate settlement records of the original owner.