Adding text to pdf document

[Rodolfo Medina <rodolfo.medina@gmail.com>]

Hi all.

I've been tried masterpdfeditor, in the .deb version from official site, and it
seems to be quite powerful.  Differently from xournal, it allows you to re-edit
previous changes to the document, whereas xournal seems not to be able to do
that.  The problem is, that it is proprietary software that asks for money
otherwise more and more `watermarks' are added to the document any time you
edit it again.  Anyone out there has experimented the matter and found a good
solution to the problem of adding some bit of text to pdf documents?  In
particular, I want to add fingering notation to piano sheet music papers.

Thanks in advance for any help,

cheers

Rodolfo