Search function

Not sure if this is the correct section for this post, so please advise me if isn't. What I am looking for is a script preferably free which I can add to my Wordpress website to allow me to offer my users a refined search option. What I mean and for example my website is selling dinning tables and chairs and I want to offer my users a way to quickly search my website by their needs, with this I want them to be able to just select the amount of seating they want, wood type and so on. Is there anything like this available?

Thanks for your time.

Enac0

If you are using MarketPress, this is the plugin you need: http://premium.wpmudev.org/forums/topic/freebie-marketpress-product-search-widget-plugin