As you may have read already, there are also the pre-washers and not pre-washers.
If you are relatively new to quilting, and you have a limited budget - start with lap quilts. There is a smaller investment - and you can learn as you go.
One of the ladies in my group is always trying some new technique with the baby quilts she makes for her many nieces, nephews, grandnieces, and grand-nephews.
I look at the fabrics I have in my stash - about 20 years worth - and I'm still happy with some of my choices - and there are some fabrics in there that wouldn't even make good rags.
As many of the other posters have said - it's a learn as you go process. But I can understand the desire to not reinvent the wheel - no need to make the same mistakes others have!