http://www.debbiemeyer.com . The machine is free if you pay shipping and handling and they offer a large lot of replacement bags for a reasonable price.
This vacuum sealer (to the right) is priced at $14.99 and includes 10 gallon bags and 10 quart bags. They are refillable and reusable till you break them and cannot make a seal. At this website you are offered free shipping at checkout and they also sell more bags. Other sites are selling just the twenty bags for $12.99, so check this out and seal everything!
I use flour seasonally more in the fall and winter and use vacuum seal bags to save the flour till I need it when I don't use it as often. It saves a lot of money and I don't worry about humidity or bugs.
Also, when packing up prep goods, vacuum sealing salt in bags and stacking it without the cardboard box makes for a lighter weight moisture proof solution. The bags stack and pack better without as much dead space in the storage container as stacking in a cylindrical box. Other spices also store well this way.
Consider a few boxes of pepper which are square-ish and several boxes of salt, with five or six round but not perfectly cylindrical containers of sage, ground chili or cinnamon and you put it all in a round bucket. There is a lot of dead space in there. There is a lot of wasted space in those corners inside the round bucket. Best tip ever: Don't forget to mark the bags even if you and an acid free card stock label inside the bag.
I have seen some bloggers using Zippered bags to vacuum seal their food for the freezer to prevent freezer burn. It has ever been the directions when using Zip-Loc bags that you close the bag most of the way then press out as much air as possible before sealing the bag shut. I have seen the use of straws to suck out air, the use of microwave cooking for a half a minute before closing the bag. There are some using bike pumps to remove air. Okay, people! calm down. press out the air with your hands and seal before freezing then date the bag and don't leave it in the freezer for years.