Hey there. I am assuming you want a script to submit sites automatically to several search engines at once.
1. Need to make a form
2. Have them input their site with description or any other variables needed (such as email address etc)
3. Make the script post these variables to each individual search engine submission form
The only problem I see with this is that most search engine submission sites have captchas now. Images that contain numbers or a phrase and you have to input this to confirm you are human. This is hard to do. It is hard to get your script to read the captchas. I am not saying it is impossible by any means, but the people who can achieve this require lots of money to make such a script.
Good luck on your quest!