sand arena/astro turf?

[Rach]

i have a large green shed like the indoor arena but prob half the size of one from a big yard ,the floor is concreate and i was woundering if i could make it into an indoor arena,how would i do that,just a tonne of sand? how much sand and how much does sand cost and iv also seen an aena made of astro turf can you really use thet for horses?and what would the cost be,im not geetig much look a finding info on suppliers and price on the net