Texturing advice

One thing I have a problem with when I am painting is texturing.  
So can anyone give me advice on how to do textures,make texture brushes and patterns without using photo textures?  
In particular I need help with texturing Metal and steel.

Are you Collin, or do you just upload pics by him?  
The tl;dr of it is that material texture is caused by how the object reflects light, and special brushes are a really small part of getting it right. I’m only just starting to even attempt it, but real artists do a lot of studying to get it right:
 
Audrarius’s Woodjack  
and Metal Dash
 
You might want to watch this though: https://vimeo.com/30702737  
But for the most part he’s only using the custom brushes the same way you’d use photo textures. And where he’s not, he’s using brushes with shapes very similar to sai’s defaults.
 
There are some great material studies on DA:  
http://modalmechanica.deviantart.com/art/Material-Rendering-Assignment-262661199  
http://xrg-artwork.deviantart.com/art/Material-Studies-405003651  
http://rpowell77.deviantart.com/art/Material-Studies-495594503  
http://b-cesar.deviantart.com/art/Study-Materials-318527071  
http://inkdotdev.deviantart.com/art/Material-Study-301999610
 
http://alphacanvas.deviantart.com/art/Effects-Using-Value-and-Saturation-279717875

@Eggonaught  
Thank you  
Also I never heard of that Collin guy.