Addding code to post template

You might be interested in Ultimate Tag Warrior:
http://www.neato.co.nz/ultimate-tag-warrior/
which can do the Technorati tags automatically, and will probably help with Google optimization.

For AdSense, I find the AdSense Deluxe WordPress plugin great:

http://www.acmetech.com/blog/2005/07/26/adsense-deluxe-wordpress-plugin/

You can easily add AdSense to your posts and/or to your templates, and you can change the ads via an easy-to-use interface. You can also add code to float the text around the side of the ad. I’ve done this on my site, and it seems to be very effective.