Yes, got some Holdons - keeping them in reserve for when I find out I've put eyelets in wrong place. I suppose I was thinking that somebody like Draper did a cheap and cheerful. Thanks for the suggestions, should get something from them.
Being a determined DIY I found that unnder stress eyelets are not so good. You can improve by puting them through many layers of fabric patches. I reckon the easiest best is to sew a piece of fabric into a strap shape and then sew this to the hem (on a corner) or well into the tarp sewing through both layers of strap and the tarp itself.
You can tie ropes etc onto the loops and double up if you need more strength. Just a thought from olewill