Legal Question in Intellectual Property in California

Unless there was something in the sales agreement, my opinion would be no.

It all depends on the sales agreement, but I find it hard to believe that an agreement to sell a ranch would include any of the seller's personal papers.

It would depend upon the terms of the sales agreement. If the journals are accounting records or descriptions of transactions, they would probably be included in the "good will" of the business. If the journals are more in the way of a personal diary, they would probably need to be specifically included.