Some reluctant recommendations from Walter, who also contributes this picture of an enoteca in Padua (where he lives) offering 'a good selection of left-field wines at very reasonable prices'.
Stumbling upon good-value Italian wines happens when you go completely off-piste and steer clear of most international varieties. Leave the supermarket behind you because, with very few exceptions, you won’t find exciting wines there because most bottles need to sell on the basis of instant recognition. Go to the independent wine merchant instead and ask for recommendations. Often they let customers taste first, something a supermarket simply cannot do.
A big obstacle...