Adsense Advice

Your positioning is good enough without going overboard and plastering your entire site with ads, but you may want to add some link units below your articles.

Also try experimenting with different color schemes, I believe people can tire of the same old blue.

Realize that not every niche is crawling with people eager to click. I've made sites that had almost zero clicks despite being ranked well.

Also, there is such a thing as trust. The days of hoping stupid people will click on any ad is diminishing slowly by the day, as more people become more educated, more aware, more savvy, more questioning. This is one of those subtle factors....like your look and feel, your trust score with people...etc, etc. So look at how you can improve your trust score, and your site, overall.

Some of my sites never got many clicks when they were new (few clicks for months on end), but today, they get decent clicks, which may indicate that "trust" is a factor in CTR. Check your bounce rate. I don't really update those sites much, but they still get decent CTR on most days, and the one connecting thing for me is the bounce rate.

Your placements look decent to me.

You might try changing the text size of the 336x280 ad-block to small (rather than medium, as I suspect it is now), and change the colour of the URL from green to a light grey or something to make it less dominant, forcing the eye instead to the darker and more noticeable (plus more normally sized) ad title links. Those changes have had a history of improving CTR for me across pretty much all sites I've tried AdSense on.

On top of that, you could try adding a horizontal AdSense link-unit to the center of the blue (or is it purple? I'm colour blind) horizontal navigation bar, in place of the existing category links. You could then move those elsewhere on the page.

EDIT: One more tip that usually seems to increase CTR is forcing the content of your posts beneath the 336x280 ad-block, instead of having it flow around them. This makes the whole ad stand out more, and will often prompt many people to click on an ad straight away if they see one that interests them, rather than starting to read your content.

This will detract from your sites visual appeal a little though, I think.

take the sidebar adsense out
put a 250x250 square under the title
make 1 post sticky on fron page
profit

Thanks to all of you who replied. I love this forum because of all the great feedback and participation.

Charlie