If you have access to the repository, you can find all files in the attic with find. Try a command like:
find . -type d -name Attic -exec ls -1 {} +
You can also list the files with the `cvs` log command. Try:
log -R
Both of these will list the names of the `RCS` files used to store the file. Remove the `,v` at the end of the file to get the file name you want.