I can’t tell you how many times I’ve had to go through the arduous task of making a seamless pattern! Well, I actually like making them, but it can be time consuming.  I found this website online that will make seamless patterns online for free.

http://www.studioludens.com/repper/

It comes out a little odd if you were to put a picture of a person in there, but for making seamless patterns of textures this rocks!

There are also online sites for making diagonal stripe, and tartan backgrounds that I have used in the past:

http://www.stripegenerator.com/
http://www.tartanmaker.com/