Boston University librarian Marina Katseva has amassed a large collection of Tsvetaeva memorabilia. This article from the BU weekly newspaper has more information.
Namen van Russen in alle talen, a Belgian site, gives possible transliterations of Tsvetaeva's name for several languages.
This Russian-English vocabulary was put together as part of a Stanford University course, to help students reading Tsvetaeva in the original Russian.
A Courtroom in the Underworld is an odd story/essay-type thing which includes an anecdote about Tsvetaeva. I have been unable to find out who wrote this piece.