Before I really got into adsense, I just dumped ads across several websites without any planning, creating channels and then deleting them. I have reformed my ways and improved my methods but think I have several 'orphaned' ads running. I plan to revisit all the sites and ads, but is there a way of tying up the ad unit to the channel using the google_ad_channel parameter to avoid having to re-create all the ads?
Aha! I have found out how to do this. Not sure if its the best way, but it works! Create an ad for each of your channels, make a note of the channel ID code and channel name. Download your websites to a folder and do a Windows Explorer search across the folder using the 'All files and Folders' and 'A word or phrase in the file' and paste in the channel code. This will return a list of files where each channel code appears. If you want to find your ads where you have not set a channel code, search for google_ad_channel =""; And you are sorted! If you have terminal server access to your windows server you don't have to download the files, just run the search on your server. If you have your site content in a database, you can still search, but using an SQL query rather than Explorer.