What's the problem? You don't have to buy the whole package- you can just pay 18 Pounds for the Easy Interview guide if that's all you want. I would suggest one could economise and drop the 'Ace the Tech Interview' book, in my view so appallingly full of errors I stopped reading it, and possibly more of a hindrance than a help.
All these years....has anybody beaten DP Davies' 'Handling the Big Jets'? Wonderful. Pray 2 minutes silence.