How to extract search query and refirect to another page

[Webmaster]

I would like to create a button that if pressed, does the following: from the current website i like to extract a search query with a regular expression (e.g. to find a 7 digit number in the
site) and then perfor a redirect to another page e.g. www.example.com?id=xxxxxxx
with the xxxxxxx beeing this number.

[Admin]

You can find/write java-script function that will find your 7 digit
number in the site and perform a redirect to another page.

And associate it with a toolbar button using "javascript: function
your_func(a,b){ your_function body } your_func("aaa","bbb")" in
"Target URL" field instead of http://