We buy rolls and just cut them to fit. As far as where to buy, we've bought them from Wally world, Publix, and Ebay. Depends on who has the best price. Also, get on foodsavers email list, they sometimes have some descent sales.
Homegrown 120 Gallon Reverse Flow, Homey, the Homegrown Kettle, 3 UDS's, 3 Stack Pro Q Excel 20, 18.5" Elderly(but not retired) WSM, 150lb Capacity Homegrown Electric and a CA gasserrrr
Bicycle Fast Polder Thermo, Indisputably Fastest Purple Thermapen, SAI Satay Grill