I am planning to read Mahabharata. Can anyone tell me a good book written in Hindi
Mahabharata of Geeta Press Gorakhpur is the most famous version available in Hindi language.
Alternatively, if you wish to read it online then you can download its pdf version from here. Note these are volumes named as Year 1 vol. 5 and Year 3 vol. 1 etc. So searching for necessary Parva / chapter is necessary.
If you want to buy Mahabharata in Hindi, then buy from Vedrishi.com here you will get Mahabharata free from adulteration, many fictionious stories. With Complete of 16 thousand of Verses. In time of Maharaja Bhoja, Only 25000 verses are available. Many controversy if you want to know then go on YouTube Channel Thanks Bharat. After Invasion of Muslims then Mahabharata verses goes in 25000 to 45000 to 80000 then last at the time in modern times to around 103000 verses.