Forgive my "newbness" on this question. Is it possible to create an ad, and have the ad show up on sites I choose? If so, where do I begin learning about targetting specific sites? Thanks.
yes, it's called Placement targeting. Not all sites that have adsense are available for it - they have to opt in (or at least, not opt out), and have a certain amount of traffic. More about it here - http://adwords.google.com/support/bin/answer.py?answer=18265
Placement targeting. its also describe here. http://www.digitalpoint.com/tools/keywords/advertising.php
Placement targeting works well for me. I use it for the Acai Berry Ads that I run so I target health blogs and things of the sort. Drop me a PM in you need help.
Placement targeting is a really great way of marketing. Put your ads right in front of your target market.
tricks need? Avoid placement targeting unless you need specific audience of target site. Bcos you will charged slightly more than your other ads...
placement targeting has been very effective for me. i am able to use placement targeting to precisely control where i want my ads to be seen (or where i don't want them to be seen!) as well as the cost of the bids. i use the placement report to find sites that are converting well (and sites that are not converting well). my best converting ad is actually a placement targeted ad that is on my competitor's website (he hasn't figured out how to exclude sites from his adsense). i convert very well from this site (and it's like taking a sale from my competitor directly).