Meanwhile I go into the bookshops, and despite all the books, there is nothing for me to buy.

I bought the Niven book because I was given a book token and couldn't find anything more interesting. Of course I could have waited but I'm not wired that way unfortunately.

I find that I am reading more short fiction than I used to and more fiction from small press publishers who are publishing more for love than money. I'm sure the factors you describe are part of the reason for this change.