I am not Russian but understand some. Out of all the Russian poets I've read I think Yesenin is my favorite.
I didn't see Russian on site (just English and Croatian). I found this with Russian versions, not with too many ads:
http://samlib.ru/w/wagapow_a/yesen.shtml
but the English translation is off. For example in "Letter To Mother":
http://samlib.ru/w/wagapow_a/yesen.shtml#a_letter_to_mother
"Ты жива еще, моя старушка?" is translated too literally as "Are you still alive, my dear granny?". Granny means more grandmother while in Russian it means more old woman, not just necessarily grandmother. So the translation from OP's link is better: "Are you still alive, my dear old one?"