I've been trying to use Google's Adsense/Adwords on my site. How do I maximize this tool? Please share your experience.

I personally haven’t worked with Ad Sense/Ad words but I’ve found Google Help to be, well helpful. Here is a link to how to improve performance of Ad Sense. adsense optimization

You might want to visit webmasterworld.com. Excellent source of everything a website designer may want to know.