Also, you can't show your ads on google.com if you are advertising outside US. The ads will be only shown in your target country, for example, if your target your keywords/campaign to UK, the ads will be shown in google.co.uk and not in google.com.
Google.com is primary for US market.
I contacted google about this and there is no way to choose which country or which google site (ie. google.ca, google.com, or google.co.uk, etc.) your quick ad test will show. Alas, you must use the more advanced tools for this.
Now, time to go add this to the "google features I'd like to see" thread!