UKH

I've got a reasonable collection of hardback books, mostly climbing (obv!) and the dust sheets are becoming a bit tatty over time. I'd like to protect them with those clear plastic sleeves, but as every book is a different size I'm not sure how to go about it - a cursory search online seems the majority of suppliers are geared up to supply industrial quantities to schools and libraries. Does anyone have any personal recommendations about what to use and which supplier they recommend?

Brodart, available only on Amazon but very good. Available in 8,10,12 and 14 inch.

I just bought a roll of (non-adhesive) clear plastic, and cut and fold it to suit. That seems to be what booksellers also do.

Can't remember what the plastic I bought was called, or from where I bought it - but it wasn't expensive, and it's worked. An art shop should be able to help I'd guess.

At the risk of promoting a single product, you might like to have a look at https://mudskipperpress.com/2020/12/06/a-love-affair-with-adaptaroll/

As Rob Parsons says, you can trim this kind of protective cover ("other brands are available") to fit your book.  From experience it can be a bit of a faff at first if you're keen to get an elegant snug fit - I tend to 'save up' books in small batches for covering to get back into practice.   Does a great job of conserving dust jackets, and helps to protect book spines and cover edges.  Worth the effort.

On one web site they list about 20 steps to fitting the stuff! Am I correct in thinking if I buy the largest size I need, I will be able to trim it for smaller books?

That's the idea Rob.  Some suppliers provide different sizes, but if buy a roll of the largest size you'll need, you just trim back the inside paper liner and fold over the plastic.  I can believe it would take about 20 steps to describe exactly how to do it, though it's not complicated in practice, just slightly fiddly.  Which is why I tend to clear the table and do a batch of books at one go so that I get into the groove and produce optimal snug-fitting results.  It is satisfying to get your cherished books safely inside a neat, glossy, durable cover.  And if you're so inclined (I didn't live in Aberdeen for 5 years for nothing ...) it protects or even enhances the resale value of your books when you or your executors want to sell them off.

We used to cover our textbooks at school with wallpaper . Not pasted on, just folded around the edges and taped.

We did the same, sometimes using brown paper. It was something we did at the start of each term. I remember recovering an ancient copy of a French textbook by Whitmarsh that I later discovered had instructed me to speak formal Victorian French rather than anything useful. Although I suppose learning to cover books was useful. 

I'm not doing that to my mint copy of Extreme Rock!

You tape the wallpaper to itself, not the book - in effect making a custom sleeve for it.

I use KPC Book Protection Ltd website.

I bought a roll of the 24cm protector which you can trim for smaller books. The 24cm covers most average hardback sizes

Thanks for all the answers folks, that's a job for the long winter evenings...