There are a few GF breads that are closer to "real" bread. Canyon Bakehouse loaves are good. It is best to toast GF breads before you use them in a sandwich; they are less crumbly. GF breads freeze well. Another option is to use GF waffles (toasted) for sandwiches. There are likely other brands, but I mostly make my own GF bread (even breadmaking machines have GF options now). The National Celiac Assoication has food options (and recipes).