If you are wanting a free web icon set, then Flat iOS iCons (PSD Freebie) is perfect for your project. Todays freebie is a set of Free Flat iOS iCons (PSD Freebie) that are perfect for apps and websites.
Download modern UI style icon file and use it as you wish to use it. The credit for this great resource goes to Dribbble.com.
If you want more icon, you can check the Free Icons.