Graphic buttons have another role in the design than just a graphic element to hold a text or link on it. It makes the link text or the form links different from the rest of the design text to allow more user friendly design for websites, applications and forms.
Although buttons need to meet with the general design style, but you can still work on the buttons source to make it more comply with the general design. Here are some different styles buttons sources free to download.
7 nice FLA glass buttons in different colours, simple interactive without using AS.
contains *.FLA 96Kb + .SWF 2,78Kb
modern button style.
.PSD (photoshop format), In vector (except the reflection)
iPhone buttons in vector
This is the vector art to fit 1.25″ buttons.A bunch of buttons that made in vector.
Amazing collection of buttons.
This is a free set of vector icons designed by BittBox for you to use in your webpage or blog (or anything else including commercial apps). The files are in AI, EPS, and SVG format, so they can be scaled to any size without having to worry about pixelation.