Wow, I'm so glad you asked, because now I have learned alot myself!
I just received my first squishy from Norton House (norquilt.com), where they have all the big name quilting fabrics, and a special section called the "fabric attic" (20-60% off original price, I beleieve). I can't compare my results with the other on-line shops because I haven't tried them. Comparing to other mail order businesses though, I'd say the shipping costs are reasonable. I don't use credit cards, so I have to be patient with snail mail....my order was here in no time, even taking into account the 4th of July holiday. I ordered eleven fabrics, and only one of them is not quite the color as pictured on the site (but it's still beautiful).
I sure wish I had a bunch of spending money, now that I see there are so many choices out there! Thank you all for your input!