Tutorial about techniques you can use to create seamless textures in Pixologic ZBrush and Adobe Photoshop. Check it out, share, subscribe to my YT channel.
I recommend to use Bitmap2Material - it is very nice and affordable software for creating seamless textures and bump maps, normal maps etc. It is very easy and intuitive to work with. Just grab some free textures from sites like CGtextures or Texturify and drag it into program.