jd1, you've got a great idea! I've been doing this for some time with great success! I've been able to get old, valuable, out of print, signed editions,..... you name it!
If your local library has a good inter-library loan agreement, you are not limited to libraries in the U.S.! Sometimes you must declare a willingness to pay delivery charges. So the more you offer, the greater the chance you will get the book you want. I have NEVER had to pay for delivery!
Our library has the inter-library loan on-line! I was able to locate sources for your book by Ian D. Skennerton on the Enfield, in a matter of seconds. ISBN: 0949749257 You can also request a copy from the National Library of Australia! ;-) BUT, your chances are better through the Library of Congress.
I don't request books from the ATF Library and haven't had any luck with the CIA in Langley, VA. BUT, I have had luck with requests I've sent to EVERY military library! The U.S. Army Military Institute has been exceedingly helpful!
If you need any help locating a book, feel free to e-mail me!
And as Hoople stated, the looks on the librarians' faces when you get your gun books is priceless! Give the girls a fruit basket or something every once in a while to show you appreciate their efforts. A librarian on your side is something good to have, if you intend on doing any sort of serious research!
DaMan