Search Engine Needed for Website

I need a search engine installed on my website. It is a large article directory, so the search engine needs to be powerful enough to index an unlimited number of pages. It must also return results quickly. The engine should be able to exclude certain pages and directories. Looking for a low price on this. Your price should include script installation, site indexing, search results page, and testing. Please do not bid unless you have experience with website search scripts.