Do It Yourself Web Diagnosis

Here are some free online tools to measure your SEO efforts.

Cubestat
Enter a domain url and it will calculate and estimate the website worth, daily pageviews and daily ads revenue of the present domain.

Google Analytics
Install a snippet of code on each page of your site and you'll receive a wealth of information about people clicking through your site, including visitor data by location, search engine phrases they used and which pages they visit most often.

Xinu
This simple tool runs a battery of diagnostic tests on your site in a matter of minutes to grade your title tags, keywords and show you how many pages and pictures you have indexed on Google images.

Yahoo! Site Explorer
This service monitors the number of links to your site and where they originate. You can also review who is linking to your competitors.