You can add your sites to the Ubuntu-Search.org search engine
At this time, the list is not directly editable. Go to the google home page and clic "Volunteer to contribute".
When your request is approved, you can add sites from your google account
In "My Services", select custom search > my search engines
choose ubuntu search > control panel
Then you just have to clic "Include Sites" and add your urls
After that, I have to manually edit the embedded annotation file before your sites are really incuded in the search engine, which may take some time, but be assured that all contributions will be taken into account, as well as requests for withdrawal.
For suggestions and comments, please use the contact form