Google has launched its one of the most popular features of Google Commerce Search, Search As You Type, as a free, stand alone feature for adwords advertisers. It is very easy to implement and would help the merchant website to increase sales and conversions.
It is only available to US-based AdWords advertisers for up to 25 million free searches annually. There is a licensing fees after the free search limit. (Get more information about our Freelance Adwords Consultancy)
Read the official post here: http://googlecommerce.blogspot.com/2012/07/introducing-free-search-as-you-type.html
Learn more about commerce search here: http://www.google.com/commercesearch/sayt/