I will mention some bookshops which I used to use in Saitama Prefecture. Because I move a few times in this prefecture, I merely go to some of these shops. This is old information, so some shops may not be now, or the selection may be changed if they exist.
When I was a student of Saitama University in Urawa, I used the book department of co-op. There is Isseido near the university, on the Route 463 and in front of Daikuma, which keeps many popular books and stationaries.
I use to use Shinseido in the building near the station in Shiki City, and Bunkyodo in Niiza City and Asaka City.
I also used a bookshop, Dan, which is between the Mizuhodai Station of the Tobu Tojo line and Route 254, the Kawagoe Kaido road. And Bookpeer on the Kawagoe Kaido road near the Kamifukuoka station of the Tobu Tojo line close later and convenient.
The other area is out of my home range. So I do not know very well. I hope you will find larger bookstores near your home, using following links of publishers' standins shop list.