ususally when sewerrs refer to muslin they mean whatever fabric you can get off he cheepy racks for like $1.00/yd
Linen or bamboo could be nice, but the best way to learn would be just plain 100% cotton. It might be worthwhile to get one step up from the cheapest, that way you won't have to worry as much about fraying.
A good way to learn about fabric, is to just go to the fabric store to explore. Look at the ends of the bolts for info about the fabrics you like. Don't be afraid to ask questions. The ladies who work at the fabric store should be able to help (sometimes)
