green request

So for the summer I want some new, comfortable skirts.  However, in an attempt to live more socially conciously, I don't want to purchase from exploitative retailers but I only have limited fundings.  I contemplated making my own clothes.  I've done it before, and skirts and some simple sleeveless shirts are pretty easy.  But where can I purchase sustainable/ethical fabric?

I'm thinking of hitting up the thrift stores so see what they have for old cotton table cloths, but are there any other material sources?

"A passive and ignorant citizenry will never create a sustainable world." - Andrew Gaines