Hello!

This entire site is well written (but by a transfem), but this particular page is about transmasc puberty: https://genderdysphoria.fyi/en/second-puberty-masc

The c/ftm community had this in the sidebar, which I think is mostly US sources for binders and the like: https://docs.google.com/spreadsheets/u/0/d/115zI3opsYcJAiygoiH0d0MIghMRz3WMcivXeDQ9wbkQ/htmlview?pli=1

I have a link to a transmasc DIY HRT guide but it sounds like that isn't something you need!

I can't get this site to work in my browser but it has gender affirming stuff if you're in europe: https://untag.com/

There was a transmasc who talked to me about a transmasc sharkey or mastodon instance at some point. That might be of interest, but I do know there are some guys here as well.