API For Onsite Search

Needed For Related Articles

[kamikaze Optimizer]

I have a PHP-Nuke article site with 13,000 articles and growing at a rate of about 1000 articles per month.

I have been struggling with a PHP function that queries the SQL DB to provide an onsite “Related Article” list.

I can never seem to get the same results as a Google search for: “site:www.MY-URL.com ARTICLE TITLE”.

Is it possible for me to program a Google API to provide this feature for me, an onsite “related article” block?

It has been sometime since I last looked into Google API, is it still limited to 1000 queries per day?
If so, can the results be cached?