I found this interesting article, newly published, with tips and also compares Herculaneum vs Pompeii. Perfect for "armchair travelers" (such as myself) ...or others who may hope to some day travel to Italy. ( Martin)
The Villa de Papyri is in Herculaneum, but I am not certain if that is open.
This article is long (be sure to keep scrolling past the many pictures/ads, as there are lots of details).
How to visit Herculaneum (and 3 huge reasons why you should) - Helen on her Holidays
Visiting Herculaneum, a Roman city destroyed at the same time as Pompeii, is really rewarding. Here's how to visit Herculaneum on your trip to Italy.