I haven't read your code yet, but if this kind of coding is new to you, definitely check out Nicholas Zakas's article, "Creating an Autosuggest Textbox with JavaScript":
http://www.webreference.com/programming/javascript/ncz/ http://webreference.com/r/pg/javascript/ncz/column2/ http://webreference.com/r/pg/javascript/ncz/column3/
Nicholas is an expert JavaScript coder with several published books.
DanB