Font Awesome - Font Awesome makes it easy to add vector icons and social logos to your website. And version 5 is redesigned and built from the ground up!
Logo Foundry - Logo Foundry is a professional Logo Design Suite App for Android and iOS that let's you create professional branding for your business in Minutes.
Nucleo - Commercial vector icons and accompanying apps to manage and customize them.
Looka - Make a logo you’ll love with Looka Logo Maker.
The Noun Project - Creating, Sharing and Celebrating the World's Visual Language
Canva Logo Maker - Create your own custom logos without having to hire a designer with Canva's impressively easy to use logo maker. Completely free, completely online.