Ok, being 6:36 am (Perú time) am DeviantART doesn't let me search for anything (so i can't provide you the links) but I do have the name of the sets so here we go: Photoshop icon is part of the set "Morning Pleasure", the Chrome Icon [link] (It's a PSD tho, you have to make it an icon) and the Trash icon is part of the set called NOD2 by Cyril Seillet
See, it's just a little trick my friend. Just place the icon inside the folder you have as a stack. For example the stack in my screenshot is my download folder so i placed the icon there and renamed it adding a "*" at the beginning of the name like this [link]
Now, right click on the stack icon on your dock and make sure you have selected "Sort by NAME" and "Display as STACK". That's all!