If you have a hardcover book in which the pages are coming loose from the spine as a whole, here is a technique I learned from my dad. Cut a piece of ugly 100% cotton cloth (ugly because you'll never see it again - no sense wasting pretty cloth!) to fit the spine of the book on the inside. Coat the inside of the spine with carpenter's wood glue, lay the strip of cloth on the glue, and lightly smear more wood glue on top of the cloth. Carefully close the book, and then open it again in a minute or two to wipe off the excess glue which may be oozing out. Once you're sure there will be no more excess glue, close the book, lay it on the spine in the bookcase, and wait about 1-2 weeks. I've used this successfully on some very treasured personal books. If you have an irreplaceable or very old book, you might check with a historian or archivist first to ask about repair or preservation techniques which would be appropriate for your book. Some academic libraries have archivists, and nearly any kind of museum will have at least one person skilled in preservation.

 Wow, thank you! I have a couple of older books I could never replace that are coming apart. Nothing anyone else would treasure, but they're treasures to me. Now I know how to fix them! 

If only now I knew a way to fix paperback books which are losing their pages one at a time! :-)

If the cover is missing completely, can you use this technique to attach a new cover? (I've got a book of fairy tales, sans cover, that I picked up off a "free" table at a yard sale a while back, and I thought I might be able to make it into a suitable present for my niece by attaching the cover from a dollar-store photo album.)

I've never tried it, haverwench, but if it doesn't work, then it's no worse off than it was before, right? This technique depends partially on the glue and cloth having a bit of "roughness" to grab and adhere to. I imagine the spine of the fairy tales is already pretty rough, so as long as the inside of the spine of the new cover is somewhat rough (which it probably will be after you rip out the three-rings or the plastic sleeves), then it could be okay. If it's slick, you might "rough it up" with some sandpaper or something.

  You need to have some book binding tape to use--we use a white binding tape that has a slight stretch to it--after attaching the cover you need to run a strip of tape to hold the cover to the first and last page.  It is visible but it does the trick.  If the spine is just broken but the pages are not tore off you can "drizzle" book binding glue down the spine, press the spine to the binding, then stand up on the spine with support on both sides for a day or two.  I have mended hundreds of books over the past 6 years while working at the public library.  This is not a proper technique for historical and/or valuable books--this is what is done to the run of the mill fiction and nonfiction, best sellers, etc. 

Hi Rolo! Are these techniques just for hardbacks? I'm having a hard time imaginging them for paperbacks. Do you know a method that would work for paperbacks? And where can one buy book-binding glue?

And where would one buy book binding tape?  

I've used Elmers Furniture Glue before, or whatever I have on hand.  You can pick up pretty scrapbook paper and rebind the cover by gluing the piece to the back of the cover and the first page.  If you do that, put the book in the center of a stack and leave it for a couple of weeks. 

To do the paperbacks, you'll need to take the pages completely apart.  "Block" the pages--bump sections of them against a table or countertop to get them absolutely even.  Then sew sections together.  If you have a small sharp punch, you can sew the entire book together.  Then reglue the cover with a little paper to hold the cover to the front page, or use your craft paper to make new inside cover and front pages.  Internet has bindery supply sites but they may not be all that essential.  I suspect that you could use venetian blind tape to glue spines. 

I did a sloppy book repair on a paperback dictionary recently. I've had it many years and both the front and back cover were so torn up with time that there was hardly anything left of them. I used an old phone book cover and duct tape and made a new front and back cover. It's not the prettiest thing, but the inside pages are protected again and I saved myself a few bucks instead of buying a new dictionary.

Edited to add: Thanks for the tip! I'll keep it in mind when I need it!