If you are looking for a graffiti style creator online which helps you to create graffiti style text or logo in just one click then there is a solution named- graffiticreator.net
This web site is a free powered by online flash application which helps you to design your own name or logotype in graffiti-style. In the Text box you can easily type your text or logo name, whichever you want to have in a graffiti look. Adjust Color style. It allows you to change back ground color, text color, text shadow color etc.
Now when you are ready just screenshot the whole generated text or logo. We also will advise you to use adobe Photoshop for more perfection. Always select white as a background color which will help you to create transparent image out of it, easily.