Icons have been around for a long while now and customized icons for the web are becoming more and more popular as time goes on. They do an amazing job to train the eye and help draw out the most important information. The most important aspect of designing an individual icon is that it has to be instantly recognizable, you have to know its function, and you need to know exactly what it is. If you are designing a set, the actual design becomes a lot harder, you have two challenges: each icon you design has to be individual and distinctive from the other, but at the same time they have to have similar features to show that they are related, making a complete set.
Here is a selection of free high-quality icons that are available use. Don’t forget to read license agreements before using icons in your designs – they can change from time to time.
PSD and PNG formats. The .PSD file has well hierarchy and is ready to customize. Also you can grab PNG images (128×128 px.) with transparent background for using straight on the web. The files are completely free for both personal and commercial use.
3D icons. Each icon comes in 5 sizes (PNG format), with Photoshop PSD files in case you would like to tweak the icons.
Each icon comes with its own editable source file (in .AI format) so that you can easily modify the icons as you see fit. The theme of this icon set freebie is centered on 3D and wooden textures.