search index page:

<%= form_tag nil, { :id => 'search_form'} %>
Search Tutorials<br/>
<%= text_field 'tutorial', 'title' %>
<%= end_form_tag %>

<div id="tutorial">
</div>
<%= observe_form :search_form, :frequency => 0.5, :update => 'tutorial', :url => { :action => 'search_ajax' }%>

Search Controller:
class SearchController < ApplicationController
def index
end

def search_ajax
  @tutorials = Tutorial.find(:all, :conditions => ["title LIKE ?", "%#{params[:tutorial][:title]}%"])
  render :layout => false
  end

 end

Search AJAX page:
<% for tutorial in @tutorials %><div>
 <%= link_to tutorial.title, :controller => 'tutorial', :action => "show", :id => tutorial.id %></div>
 <div><small>posted in: <%= tutorial.category %> by <%= tutorial.username %> on <%= tutorial.date %> </small></div>

<% end %>