If you are looking for some great social media icons, let me recommend two names. You might also want to follow them on Twitter, Dribbble and what not.
Gedy Rivera’s absolutely stunning 155 vector and custom shape social media icons are amazing! This vectorised icon goodness, available in EPS, CSH and SVG formats, will not let you down. You can use the icons for both personal and commercial projects, and you get free updates.
Rogie King’s basic social media icons are similar to Gedy’s and are just as sweet! You can pick any variant you like of the basic flat icons that are optimised at 32 and 64 pixels in five different styles (circle, rounded square, square, symbol and monochrome. All files are semi-transparent PNG bitmap. In total, you get over 1100 icons, and you can try out some free icons before you purchase the whole set, too!