where can I find guze like fabric need to make an purse of different colors

I would think you'd need to check at a regular fabric store like JoAnns instead of a quilt shop. It may be in with the dressmaker fabrics.

They have a gauze fabric called scrim in the home dec fabric, for curtains.

If you are willing to dye your own, Dharma Trading has several types of gauze and gauze-like fabrics for very reasonable prices.