Now it sounds like a usual stuff spoken everywhere, You Search Google for keyword “SEO” and there`s about 7,110,000 possible results . but one thing I noticed about my site in SEO is that after I changed to blog, the traffic from search engines are immence .
Few Links :

~ SEOpapers :
~ Google Information for Webmasters
~ SitePoint Forums

Now , few stupid things by me ,

~ IF u are in real need go to Google and search for the key word your site is related with and keyword “forum” with it. join the first few forums ,obviously they should have high page rank and then –> SPAM .. lol

~ Start a Blog , I noticed that Google/MSN etc. are pretty bhai-bhai to blogs , they get listed fast . (Though it does not do much updation for free blogs , I think) or use Mod Rewrite for other Content Management System`s.

~ Never trust/pay SEO Firms Blindly! infact I would say don`t even go for it , Optimisation depends on your site , it`s content and the popularity it has .If you visit Google`s SEO page for Webmasters , you can see a clear para stating

Some SEO’s will promise to rank you highly in search engines, but place you in the advertising section of the engine rather than in search results…….his scam does not work with Google because our advertising is clearly labeled and separated from our search results, but be sure to ask any SEO you’re considering which fees go toward permanent inclusion and which apply toward temporary advertising.

It`s better to do it yourself ..

An article on Website Customization and Search Engine Optmization