There are lots of El Burns videos on quilterstv. She also has some videos of her methods at her web site, Quilt In A Day.
She has special rulers for doing flying geese that are a must once you are more knowledgeable.
So many experts push their products and rulers that it can get very expensive. I found that the squares for HST is the best way and no special products or rulers involved.
If you need a different size HST you just add 2 in for each size. 6 inch makes 2 1/2 inch, 8 inch squares make 3 1/2 inch HST, 10 inch makes 4 1/2 ect.
Be sure and watch Billie Lauder videos too. She has some quicky methods.