The making of a raised flower bed

There is this one area at a corner of our little garden that I have cleared up and uprooted all the grass.

It was hard work, no kidding.  But with proper tools, it was bearable.  The plan is to have a raised flower bed, something like below, but not in a circular shape of course.  However, until now, which is more than a month since the project started, the flower bed is nowhere to be seen and the corner remains bare.

I have difficulty in finding the kind of stones that I want.  I guess I was searching using the wrong term.  Only recently that I got to know the right term for such stone.  It's called the retaining wall block.  Hope to be able to give some positive updates on this soon :)