If there were more stands with local produce and meat, this would be a slam dunk 5-star review. You haven't been to Cleveland without a stop here.
Be aware that some of the fruit and vegetable vendors may pawn off near-rotten produce on you if you're not careful. Select yourself when able, and find a stand to be a regular at. Personally, I go with Tony's Produce for fruit, and DeCaro's Produce for vegetables (but anything in the half-empty eastern portion of the produce section is great).
You cannot go wrong inside. Every store and stand has something delicious, check out as many as possible! If you're going to go on Saturday, go early to avoid the huge crowds.