Enter your telephone number at https://www.btwholesale.com/adslchecker/
and at the top it will tell you which cabinet you are connected to.
You can then find the cabinet by going to https://www.telecom-tariffs.co.uk/codelook.htm
Enter the first 7 digits of your full phone number, click Lookup Number, click your entry under "Locality or Use", then it should have an option like "all <number> fibre cabinets" to click: then scroll down to get a list of all the cabinets and their locations. (Note that the cabinet location is just a postcode, and the point shown on the map is the postcode centre point, not the actual cabinet location)
For your neighbours: use the first link above but click Address Checker (*not* Postcode Checker), enter the postcode, and either enter their house number or select their property from the list. Of course, if you know their phone number then you can enter that instead.