Some smaller libraries will search specific items for specific people for a nominal charge or just the cost of copies. It can be a good way to get access to material you may not be able to access otherwise. Many genealogical publications (especially out of print books that are still in copyright) can be difficult to get online or via interlibrary loan. If you find that a library has a copy of that unusual book, see if they will search it, copy the index, etc.
It is worth a try.