In your Custom Search Control Panel you have many more options built into Site Search within Google Sites:
Basics - Search Box Description , Language and some Preferences
Sites - Active Sites called from Web Master Tools.
Indexing - Indexing Statistics and Re-indexing
Refinements - Refinement Labels - a form of tagging. Adds 'refined' search tabs to Search Element (mini site) and CSE page searching.
Promotions - Promotional Information Triggered for Search Queries
Synonyms - Variants of Search terms - Grouping terms
New* Auto-completions - Automatically Suggests Search keyword directly in the Search Box - Custom Auto-completions Add/Hide Keyword Terms
Look and feel - Design Layout
Get code - Search Box Code
Collaboration - Invite Collaborators
Make money - Show Ads from you Google Adsense
Business account - Business Site Search paid search engine - ad free and even more options!
Advanced - Annotations - XML Context upload Rich content additions - Promotions download.
Preview - Preview your Site Search Box
Statistics - View Day/Week/Month/Overall Search Queries linked to Google Analytics.
CSE Gadget Example - The CSE Gadget is available for your Custom Search Box when it is created.
You can simply embed the following Custom Search Engine Form directly into Google sites.
Changes the yellow Elements.
Replace the Website with your Google Site.
Get the cse id from the CSE search
CSE Search Element which provides realtime search results in the same page.
Searches tab: Multiple Search Boxes
Opening a new page for the Custom Search Engine with the choose of site search or web search.
Custom Search Engine Example
The Google Marker adds more functionality to your Custom search engine .
With the Google Marker Link you can Add Sites , label Sites and annotate your Google Site.
In the "Goopal Toolbar" Google Gadget above drag the Link "Google Marker" into the address bar of your Browser.
You can Annotate (Tag) your Google site for the Custom search Engine.
The annotations options for www.goopal.org for example:
These annotations also appear as tabs for the CSE Search Element and Links for the Standard CSE Web Page Search.
Internet Explorer users: Right-click on the marker, then select "Add to Favorites" > "Links."
In Custom Search Engine you can enable/disable the Auto-complete feature. the autocomplete is triggered when typing within the CSE search Box.
You can define the keywords for your automatic suggestions or even disable keywords.
Search: CSE Search Element