Can anyone help me with a good list of php site search engines. I am thinking of implementing a google site search, but I would rather not pay for that and I would rather have as much control as I can over it.
Read through Roll your own Search Engine with Zend_Lucene.
The article is rather old though, so have a look at the ZF Reference Guide about Zend_Lucene too. Searching for Zend Lucene on Google should yield plenty useful results too.
Sphinx is pretty good, but it isn't written in PHP. It has got PHP libraries to interface with it though. You could also have a look at Zend_Search_Lucene from Zend Framework. Both of these make search indexes so you can do fast searches.
You can try the Zend Lucene implementation:
http://framework.zend.com/manual/en/zend.search.lucene.html
http://devzone.zend.com/article/91
You don't have to pay for Google Site Search and there's a small chance for much control means greater quality of results.
If your site is very specific you need to write you own code for search.