Hi

I'm in the middle of planning a documentary film intended to be used for online use. I have contacted a couple of producers who produce indie/electronic music and they have said they are happy for me to use their tracks.

Do I need to do anything to cover my back incase I get questioned, or the producer trys to sue for copyright? Will a print screen of the email suffice?

Cheers

Get them to sign a release form saying that they are allowing you to use their material and if they agree to do this for free state that as well.

Make sure everything is dated and signed and list how long you want their permission to last. Be careful if there's anyone else involved in making their tracks and the permission includes theirs too.

For safety, store copies with your family solicitor.

Cheers.

You must make sure that you have a written and signed agreement with the copyright owners of any material you intend to use in a film. Don't overlook the importance of doing it.
I wrote a basic introductory tutorial on the subject of choosing and using music in video, which is here:
Choosing And Using Music For Film And Video | Rocksure Soundz (http://rocksuresoundz.com/2012/04/19/choosing-music-for-film-and-video/)

It outlines the possibe ways of obtaining music for video/film etc, the benefits and pitfalls of the different choices.