Re: Alternatives needed
If you're after second hand books then a *really* good alternative to amazon is Abe Books (other 2nd hand book sellers are available). Lots of British second hand sellers list books there, alongside a great many American ones too.
I've bought old out of print books from there many a time, and often for a tiny sum. If you don't mind waiting a couple of days for postage it's reet good.
As for tech goods, generally you can get stuff (even your 400GB SDXC card) with a little dilligence. You might pay the 'not amazon' tax, but I suspect that it's probably not something that's going to trouble you if you're dead set on denying Bezos your hard earned dollar/pound/euro/etc.