Pompeii

We used Walks of Italy for a 3 hour tour that was excellent. The guide was extremely knowledgeable and made things come to life. Groups are limited to 15 people and everyone gets their own headset so they can hear the commentary. The cost is $65 and you meet them outside the gates of Pompeii. If you are trying to do this from Rome, they have a day trip of Pompeii and the Amalfi Coast, also.
www.walksofitaly.com

You can also show up at Pompeii and hire a local guide. I believe there is a set price and they have to be certified to do so.

I don't have a specific company to recommend, but you'll want to be aware that the Pompeii archaeological zone ("scavi") comprises an entire city. It's very possible to walk, walk, walk for hours and still not see everything. I would recommend ensuring that your guide will take you out to the Villa of Mysteries and not just stay in central Pompeii scavi.

Are you looking to do this as a day trip from Rome? If so, your time at the scavi will be limited. If you will be staying in the town of Pompeii or somewhere in the local area, then you'll have more time to explore.

I went onto Viator and found the company which offered the specifics I wanted in a tour. Pick up at hotel - yes/no? Lunch included - yes/no? Hike up the side of Vesuvius included - yes/no?

As I recall you can pay for a guide at the admission gate.

The first time I visited Pompeii was in 1983 and we did it on our own with a guidebook. The second time was in 2012 with a guide. With a guide was a little better, but not huge.

Glad to hear you enjoyed the Walks Pompeii Tour, va from va. We have the day trip
from Rome with the Amalfi Coast stop booked with them in April. Looking forward to it!

There are guides working there at the entrance.

The best, in my opinion, is the Rick Steves recommended Gaetano Manfredi. His website is a bit hokey, but he is fabulous. He comes from a family line of guiding in Pompeii. He is expensive, but a worthy splurge. There are no other tourists with you as it is private and therefore very personal and efficient.

We used another "highly recommended" company the second time we went to Pompeii, also for a private tour, which cost about half of Gaetano's fee, and she was horrible. We could hardly wait for her tour to end.

We're do-it-yourself slow-travelers so we have twice based in Sorrento and taken the train to Pompeii, just wandering at our own speed using the RS walking instructions. (And once went from Sorrento to Herculaneum, also self-guided.) Sometimes eavesdropping on other people's guides ;-)

The Pompeii website has a 'complete' map and a large PDF with descriptions of each of the 'places'.
http://pompeiisites.org/en/visiting-info/map-and-guide-to-the-excavations/

I printed it all out, have read it all, marked the map for the major houses/temples/etc which we KNOW we want to see.
I'll carry the printed out PDF (which MAY match the pamphlet they give us for free at entry, but mine is marked up).

The goal being to knowledgably wander around on our own.

This map is of the general Pompeii and Pompei area.
http://www.unicocampania.it/files/mappe/pompei.pdf

We found the RS audio tour very helpful

We did City tours and was very pleased. We toured in Rome, Venice and Florence.