Webscriptlab.com offers a free tool that can help you generate a loading gif animation for using in your AJAX web application. This tool can help you create your own Ajax loading gif easily, you just simply select indicator type (such as circle ball, arrow, bouncing ball, bar, clock, 3D rotation, wheel, big roller and more..) then select background color, foreground color and speed and click on generate button.

Link : Ajax Loading Gif Generator Online