A relatively complete article with pictures -
Love those new cooling fins - also a great technical article on slowing down and reducing the noise of cooling fans. A potentially dangerous idea for the novice. But not as dangerous as ye olde liquid coolng schemes I've seen in past years.

One thing that keeps getting missed in these articles is that the number one cooling problem I see in home grown machines is people blocking the airflow within the case with badly placed ribbon cables and failing to put in case fans in the tops of towers to pull out the hot air at the top where it tends to drift anyway. There was once a really good ribbon cable rounding article here - again - another dangerous article for the novice - but definitely worth a look to resolve airflow issues in a hot case.