If I ever decide to write a book, how do I begin to get permissions for images/stories to be used?

[Mysticpuma]

That is a huge question and I realise it could have a huge answer too, however my reason for asking is that a lot of the images I have were taken by the USAAF. Some have since been published in books and others have come from family members or relatives.

Firstly all the interviews I have conducted I would presume are my copyright, but to quote from them do I need a 'model release' or can I just get written permission (or do I need any)?

Secondly if pictures, information and stories have been previously published is there a set procedure for getting permission to use their material (I realise I can't just copy it!) and if the company who published it no-longer exists...what do you do then?

Lastly, is it worth the effort? I realise that some military aviation books are very sought after, but I also realise that is because the runs are limited, so they are much more 'wanted'.

I have no knowledge of publishing a book, but think that the stories and anecdotes I have managed to gather in 5-years of researching the 325th Fighter Group "The Checkertail Clan", may be of interest to some?

Thanks for any advice, cheers, MP