As you all know in this huge internet world its always tough to find the best resource in right time. So as and when I came across some good resources I just save it for my future reference and sharing the same with you all via WittySparks.
The team at Custom Icon Design will provide you a professional touched set of icons for your design website or applications. I would recommend you to check their awesome portfolio to find out what they can do for you to enhance your applications.
If you want to check their quality of work, they have around 9 excellent set of icons for free to download.
These are the following Icon sets they have for download and use under non-commercial use:
All the above set of Icons are rendered at 256×256, 128×128, 64×64, 48×48, 32×32, 16×16 pixels and format are png, ico and icns.
Liked it then spread it :), let us know if there are any good icons to get featured in wittysparks.