Books I repair myself are mostly children's books, well-loved and hard to replace, but with no exceptional monetary value. I don't re-bind them, only fix covers and pages. There are excellent binder shops, like Bessenberg Bindery in Ann Arbor, for major repair.
Minimal book repair materials: Filmoplast P paper adhesive release liner mending tape, 3/4" or 1" wide. It is archival: paper and adhesive are acid-free, will not turn yellow or stain pages. Siliconized liner peels off releasing thin semi-transparent tracing paper-like film that turns invisible then burnished into page. Can be used for T-hinges for photographs and lightweight art, too. Transparent mending tissue by Lineco, Archival quality, 1/2" wide is very similar. It is thinner as well as narrower, and useful for finer papers. I found impossible to handle it without a burnishing bone.
Lineco linen hinging tape 1" wide is strong fabric based tape with gelatin water-based adhesive. It can be used to reattach the cover to the block, and can be safely removed later if you decide to attach real endpaper.
Burnishing bone: a flat smooth stick about an inch wide, 1/8" thick in the middle, with flat end and pointed rounded end. Used to flatten adhesive tapes and press into paper, to unfold and smooth small folds, to smooth fine creases on the paper. Very useful for framing, as well.
Clear polypropylene archival acrylic-adhesive tape, like Gaylord Crystal Clear 3.5 mil strong, 3" wide. It looks like any plastic adhesive tape, but it stays clear and adhesive doesn't dry out, or so it claims. I only used it for five years, and there are no changes yet. I use it mostly to reinforce the spines and corners of new laminated books.
X-acto knife and strong fine-tip precise scissors, good to have at home anyway. I use Fiscars and Tweezerman LTD. Don't use scissors for mending tape: it will stick to the blades and to itself. Tear the tape instead. Torn ends blend with mended page better.
Tubular book jacket cover: polyester film roll, 2 mil, comes 9" to 16" wide. It is clear, flexible, it gets creased then folded and pressed. Absolutely archival and safe for the books, removable, since you don't attach it to the book. I use it to wrap all but leather-bound books.
See also: picture framing.