What is everyone's opinion on where to place large ads (eg large rectangles) if the site has no margins as such. On the left or right side of the page? I have a large rectangle placed on the left of my homepage at the moment.
You can use A/B testing for this (if you know php)... and you'll see which position gives you more money.
Thanks for the tip, but I don't know php. The exact position of larger ads seems to make a big difference to CTR. Experiments with position will tell perhaps.
According to the Google heat map, put them on the upper left. Here's the heat map link. Google Heat Map
Yes thanks for pointing that out. Top Left seems to be the best spot, though I wondered if changing the position every week or so would increase CTR.