Depending on your website the search box might be a crucial element of your site. Ultimately having a functional and aesthetically pleasing search section is helpful to your end users. Drupal's built-in search module is a good starting point but if you have lots of nodes your site performance might take a hit. You can try using Apache Solr Search or Search Lucene. Aside from the back-end configuration how does one theme the search box in Drupal?
Well you can theme the search section in multiple ways: search block (/admin/build/block/list), search page (/search), or the default theme implementation ($search_box). I'll be addressing the theme implementation.
- Make sure in your page.tpl.php your theme prints out $search_box
- Go to modules/search and copy search-theme-form.tpl.php and paste into your theme folder (In the comments there is code to see what's available to you in this template.)
- Modify the output as needed
- Add styles and interactivity.
Personally I like to remove the text, "Search this site:" increase the search box size. Additionally I think it's good idea to add some default text into the actual text field (i.e. Search by Keywords). Then using jQuery remove the text once a user clicks into the search text field and add the text back once they click off. You can finish out by adding some CSS. For example a light gradient, or 1px border, or a nice background. Attached is the search template and script, hope it helps.