I bought one at Wal-Mart (can't recall the name but it seems to be the most popular one there). Anyways, I find that the no-name type bags don't work as well as the name brand ones.
I use the vacuum sealer for everything. When I smoke a pork shoulder and make pulled pork I divide up meal size portions and vacuum seal and freeze them. We take them camping and re-heat the bag in boiling water and it comes out perfect.
When we went on our 3 week journey last summer I vacuum sealed a bout 5 days worth of dog food per bag. That allowed us to store the smaller bags in easier places than to carry one massive bag of dog food.