I'm afraid it is impossible, even with a paid for program. Most likely your pdf-files are just something like a 'print' to a file. And in that 'printfile' it's not possible for a program to recoglise the headers and such that you want to index or bookmark. You need an editable version to mark those headers. Using the original word processing file would be a good start, but wouldn't allow for making that index with a free program.
However, you can have a look at the pdf toolkit from http://www.pdflabs.com/.
It allows for merging pdf-files and importing bookmarks from a file you have to make yourself. The lay-out is described in http://www.pdflabs.com/blog/export-and-import-pdf-bookmarks/
It seems a lot of work.
Kees
Hi
I have several PDF's that I want to merge into one large file & then create some sort of indexing or bookmarking capability on the side, similar to this example. I need it for either Windows 8 or Ubuntu 12.04 OS edition. Of course, the software or tool has to be a freeware or at no cost. I don't want to spend money for this case.
Please help me out if there are any.
Thanks!

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