Look in the directory '/etc/vsftpd' and look at the file 'vsftpd.conf'. You can set the root directories for anonymous and also for local user default directories. Ther is also a man page for vsftpd.conf. I have found little else in the way of documentation, but the man page was very helpful in getting it to work properly. By the way, I have been told and the docs say to put the vsftpd.conf file in '/etc' but could not get it to work properly unless in '/etc/vsftpd'.
Hope this helps.