1.Clear Icon Set
It is a pack of stylish and minimalist icons a little small but very good quality, the author also includes the PSD files in the download. Download.
2. Broccoli Dry Icon Set
108 minimalist icons prepared for retina displays, all contained in a layered PSD file. Download.
3. 108 Monkey Icons
108 package monochrome icons that its author invites us to color if we wish. Available in 32 × 32 pixels. Download.
4.iPhone Icons
Collection of 160 icons that the author invites us to improve if we can. They are distributed under a Creative Commons Attribution-Share Alike 3.0 license. Download.
5.Token Icon Set
A pack with 128 icons in two versions: dark and light. It has PNG resolutions of up to 128 × 128 pixels. Download.
6. Minicons
Pack of 30 gray icons of 16 × 16 pixels. It has a paid version that extends the package to 110 icons. Download.
7. Impressionist Icon Set
Elegant and sober icons. There is a paid version, but the free one may be more than enough. Download.
More information - Ligature Symbols, a really interesting pack
Looking a lot are the icons that best suit what I was looking for.