How do I add a "search" button to my site

Answer 1

if you are using office live site then use bing search bar, which you can enable in site desinger panel.

if you are using some other host then better use Google custom search instead of designing your own.

http://www.google.com/cse/

if you still want to design your own search then use below tool, this uses google api
http://www.digitalpoint.com/tools/search/