The cynics among us might think that was a thinly-veiled self promotion TC:rotfl:
Anyway, on the subject of shopping for books, here's a great site I found which is good portal for locating out of print books. I've managed to pick up some titles which I thought I'd never find for sale anywhere via this site, it's well worth 'bookmarking' this one:
https://www.abebooks.co.uk/
Chock