I agree if you are talking about the bobbins with cardboard side. I bought some but never was very successful I like the clear plastic sides. I buy mine from marathon.com. Flowers all around.( It's 72' hear makes me think of flowers & Springtime .)
ebay is were I get all my thread and most of my other items. Just ordered 20 pastel color thread for $28.00 shipping too. 10 yard of thread netting for $13.90 shipping too,and I use alot of buttons in crafts and sewing projects got 100 buttons for $4.94 shipping too. as you can see I buy alot off ebay, and never been disappointed, by I read about the company that I am buying from. and never buy from the ones that do not use pay-pal. and order from the ones that have 100% recorded on sells.
Good advise on the "sideless" bobbins. I had a gift of these a while back, and can not use them in my Viking. I usually rewind them - just not to waste the thread. www.shoppesrule.com is another good source. About $32 for a gross of prewound.
I think ebay is a good resource for embroidery stuff. Thank you and a Flower