I looking for an extension which provide title's first character searching via Alphabetic and digits search box.
See the example below:
You can try the Search Autocomplete and Suggest extension by Aheadworks that is able to provide search results as soon as first three characters are entered into the search box. Search results appear immediately using AJAX. And, it manages both alphabetical, digital and combined searches.
Search Autocomplete and Suggest product page - https://goo.gl/8zT2VH