Any guides (organizations) in Nagano Pref?

Hey everyone,

I'll be traveling to Japan this summer with my friend and I'm looking for a guide to accompany us for one full day on our trip to Nagano Pref.

We'll be going to Nagano by taxi from Tokyo because that would save us much time and I was thinking of getting a guide to join us from the start, but that might be difficult as we will be spending the night in Matsumoto and therefore will not be returning to Tokyo.
The other option is to pick up the guide somewhere in Nagano Pref once we get there, or to meet up at one of the sightseeing spots.
We haven't really finished planning our trip yet so not sure where exactly in Nagano we'll be going (Zenkoji, Kamikochi, Matsumoto Castle etc, other recommendations welcome!) but we figured going by taxi would get us to places buses can't and a guide would give us insight and information about those places that we wouldn't get otherwise.

Does anyone know/recommend a guide, guide organization or something like a guided tour in Nagano Pref? Thanks!

For Matsumoto and Nagano City, yes. And free. You just need to pay for any transport, admissions fees and meals.
https://www.japan.travel/en/plan/list-of-volunteer-guides/

That said, taking a taxi from Tokyo to Nagano is insane. Not to mention completely unnecessary. Take the train to Nagano City, Matsumoto or wherever you are going to, and if you need a taxi from there, then fine. It's about 225 km from Tokyo to Nagano City - a taxi would cost more than your airfare. Plus you can get there in only about 90 minutes by bullet train - which goes around 260 kph.

In actuality though, you really don't need any guides. Just do your research and you can do fine on your own.

We'll be going to Nagano by taxi from Tokyo because that would save us much time
Ummm... I hope you mean that you will take the Shinkansen from Tokyo to Nagano and THEN take a taxi. A taxi directly from Tokyo will be prohibitively expensive AND much slower than the Shinkansen.