The easiest way is probably a fat quarter pack from a single fabric line. I don't do that, myself, but it's enormously popular. The books featuring that method are the hardest, for me, to translate into other fabrics, as they seem to rely on the "blendedness" of a single line to work.
More fun, IMO, is choosing a neutral and a few contrasting colors. Many quilt patterns use that combination.
If it makes you feel any better, I finally figured out what to do with a collection of pale pinks and peaches, after staring (or more correctly, glaring) at them for 2 years. They were beautiful together but bafflingly close. I kept adjusting the mix and auditioning fabrics from my stash until I hit it.
I will say that I felt enormously better reading that Kaffe Fassett had trouble picking out fabrics for very pale quilt in one of his books. It's fairly easy to do a lot of pale prints in different colors if they have a common white ground, but get them really close and blendy, and it can look like a blur.
hugs,
charlotte