How do you do?
I'd like to offer my help on this project and it seems I represent quite a unique quality as I was able to see those changes in Moscow like in a flashlight of periodic visits there while living since 90-ies in the US. I am in my 60-ish, grew up in the USSR, in the very historical center of it. I love my native city, I use to take long walks when visiting, feeling dissolved in it and feeling energized as familiar places invigorate my spirit with memories. I have even taken a course of guide-interpreters back in 90-ies.
I was visiting almost every year, stayed for a year twice and during last year in was in June and this February. As for bookstores, they are always included in my list - to get some book, a calendar or else for a present to my family and myself. I know many of those, this February it was an extended visit of a famous store on Mesnitskaya. I have been taking a lot of pictures city all the time, as well - would be interesting to fetch for old ones on paper. But best pictures of changes are in my visual memory. And I love to get a coffee and a bun while on walks (in any town) and have collected those changes in my memory too :)).
As for the books, me and my son have a good knowledge of those - we order children books and some for us online. Actually, I've recently bought V. Prakh's famous "Coffee shop" (Kofeinya)! (ha-ha)
I think I can see well the idea of your project, but would like to know what parts of it you would need some help with.