You can check here:
you can convert any of your icon to xaml
use http://vectormagic.com/ to trace image (to convert to svg) and then use
http://inkscape.org/ to convert to xaml (not sure, but inkscape can trace image too)
Try this one.
Hi at http://www.xamltemplates.net/ you can find XAML Icons .. but not for free.
Grafile 2012 Icon Collections for WPF, Silverlight Applications
Microsoft Expression Design (.design) XAML Silverlight 3 Canvas, XAML WPF Resource Dictionary, (.xaml), XAML Silverlight 4/WPF Canvas, (.xaml)
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