Bookmarker is an Adobe Acrobat plug-in. It is easy to use. Just:
Using BookMarker is as simple as that. In the Bookmarker dialog you can create multilevel bookmarks to any depth easily and quickly. Using the TextSelect tool from the Acrobat toolbar, you highlight a sample of text whose attributes are used to define a particular bookmark level; for example, a heading or sub-heading. Other bookmarking tools limit your ability to create as many levels as you wish; BookMarker has no such limitations.
Used in conjunction with TOCBuilder, BookMarker gives you unrivalled power and flexibility. Once you have decided how you want the bookmark levels to be set, the settings can be saved for reuse
A tryout version of the product is available.