With a little help from this forum, I added Google Adense to my web site and would like to share my results after almost 1 year.

Text Ads outperform Display Ads. I set up my web site to feature display ads at the top, but they were not that effective. Instead, I added rotating Colors to normal Text Ads to make it "look" like a normal 468x60 ad and click-throughs increased substantially, but still not as good as Text ads embedded in content. Having a few Display Ads does make the site look nicer.

There is a limit to how many Clickable links you can have. I was adding various text links to direct visitors to more profitable pages on my web site, but that reduced clicks on AdSense Links. I was also adding links directly to my Affiliate sponsors which had the same effect. You need to strike a balance between money you can earn from Affiliate links and Adsense Links. Adsense limits their own exposure to 3 units per page with good reason.

More Content isn't necessarily better. I am adding from 1 to 4 new or updated pages a week, but Adsense revenue has been falling. There is no direct correlation. I now have over 200 pages and keeping them updated is a challenge.

Better navigation features don't always pay off. I was encouraged to add a Nav bar to every page, which was a lot of work. Clicks within the site did not change and Adsense revenue actually went down.

AdSense for Search increases revenue.Yes! While it doesn't add much, the few dollars extra put me over the $100 monthly threshold more than once. A "Search" box should have increased visitor time on the site, but it didn't.

A Blog will increase revenue. Very true! I already had a "news" page on my site, but when I moved it to Blogger, Adsense clicks were MUCH higher, maybe 5 times. A real Blog seems to give you more exposure.

Be consistant and you'll make more money. The more you do of what you do, advertisers will bid higher to be on your site. Early on I had clicks pay just a few pennies, but as my site got better known by advertisers, the per click income got much better, some measured in dollars, not pennies. This partly makes up for lower Click numbers over time. Also, the few additonal cents earned "per impression" also gets you to the threshold sooner.

Don't over filter. I filtered out all my affiliate sponsors from AdSense, but got fewer content-related ads. I put most of them back in and affiliate income was unaffected. Early in the AdSense program I was filtering out some obtuse, and in some cases, offensive, AdSense ads. Over time, they disappeared as the "regulars" appeared more often. Also, it seems the big money comes from advertisers who are on the "fringe" of your site's subject. For example, a site about cars would mostly get ads for consumers, but a few ads directed toward car dealers or mechanics would yield higher per-click revenue.

Referrals aren't worth it. I get almost no money for "Referral" ads, and most of them don't provide the more profitable Text units.

Place ads "Above the Fold"? Nope. I redesigned the whole site to show a smaller masthead at the top but with no results. The best performing ads are still those Text ads which are placed within, around, or even at the bottom of my content. Not only are these below the fold, I design the page so the Colored Text ad at the top and the unit below the fold are never seen on the same screen, so it's even farther below the fold. The "hot spots" they show don't necessarily apply when you have compelling content. Nothing beats text units integrated within your content with complementary Link colors.

I hope sharing my experience will encourage others to do the same. I have learned some vauable insight here.