Yesterday I found easy and very powerfull trick how make nice tiling (repeated) texture with Photoshop.
Take photo, which you want used as repeated texture, (in this case I want repeat just in both sides)
Before, I cut it and its ready for process.
Next, I change size it to rectangle
and crop it...
Second step in Photoshop, go to Filter / Others / Offsets
After this you just need used Clone Stamp tool and repare midle texture as you want...
And wuala, you have new tiling texture with nice edges.
PS. you can also used and horizontal and vertical offset and make grass or others background textures...