I do...I get it from office depot and it is
http://www.officedepot.com/a/products/341669/Pacon-35percent-Recycled-Plain-Newsprint-8/

not at my staples..I have to order it online from Office depot!

What is the benefit of vellum vs. newsprint? What should I look for if I look for vellum for paper piecing? thank you.

I just cut the paper to fit it works okay.

check out uline.com they have newsprint for packing in several sizes and on rolls.

It is also super for cleaning windows. Doesn't streak and cleans exceptionally well. A professional window washer told me to use blank newsprint, but newspaper works also. Glad to know it is good for paper piecing as well!!! I get it from storage unit busnesses.

Vellum is somewhat transparent. This works for me because I don't stitch through the paper, I fold on the stitching line (which I can now see, since the paper is transparent) and stitch right next to it. Saves me from all that tedious tearing. Saves wear on the needle, too.

I simply purchase the vellum sold in my local Office Depot. I know other quilters use a certain weight/thickness, but I'm not sure what that number is.

I just keep a watch behind the Newspaper building and they throw out huge reams of paper. I guess after they get so low they throw them out, but there is so much still on the roll

newspaper ream
 

Try your local newspaper. They will often sell you some.

End rolls are probably cheaper, but I have bought kid's tracing paper at a store we have called Fred's. It's 8 1/2" wide, but I had to put the end through my paper cutter to make it 11". It's great for paper piecing, tears easily. And if it is a little longer or shorter than 11", it still works in the printer with no problem. It was a buck per tablet.