Uploading images so that they are searchable
To include image data in the core search index, you perhaps could implement hook_search_info and hook_search_index to add the custom image field text attributes (alt, title text etc..) to the search index.

You can then theme the output of the search results by overriding search-result.tpl.php or using hook_preprocess_search_result to add the image thumbnail.

Further core Search API docs here