Google Suggestion

i would recommend using Jquery AutoComplete

here is a nice sample Url:

http://www.pengoworks.com/workshop/jquery/autocomplete.htm

it requires to js

	<script type="text/javascript" src="./lib/jquery.js">script>
	<script type='text/javascript' src='./lib/jquery.autocomplete.js'>script>

you declare the Channel to the ASHX which is the Handler talking to the db 
like this:
 $(document).ready(function() {
	$("#CityAjax").autocomplete(
		"autocomplete_ajax.cfm",
		{
			delay:10,
			minChars:2,
			matchSubset:1,
			matchContains:1,
			cacheLength:10,
			onItemSelect:selectItem,
			onFindValue:findValue,
			formatItem:formatItem,
			autoFill:true
		}
	);

and thats it