And, of course, we have the excellent first-hand accounts of Alexander and Ann Shulgin in PiHKAL; which covers many psychedelic drugs and notes their effects at varying dosages. (It also covers synthesis.)

Widipedia article here:

https://en.wikipedia.org/wiki/PiHKAL

Electronic copies of the book used to be widely available online, but I can't vouch for any links that have turned up in a quick search a few minutes ago. Hard copies are still available, and are probably more complete and/or safer.

right but also https://twitter.com/erowidrecruiter

Erowid is absolutely one of my favourite places on the web