www.allstitch.net
kenssewingcenter.com
have purchased from them for several years. I occasionally pick up stabilizer at Hancocks, Hobby Lobby if they have a great sale/coupon. Yesterday, I purchased a roll of Sulky Peel n Stick from Joanne's (first visit to new store here) at 50% off plus additional $$ off coupon.
Just a note: All stabilizer is not created "equal". Depending on type and use, some work better than others.