Looking for cheap sand!

[impreza]

Hi,

I have been out of the hobby for a little while now and just getting back into it. I am looking for some sand to put in my tank. Where is the cheapest to buy sand nowadays? I used to have bucket loads, but I threw it all away a while ago .

Also, I plan to have a thin bed of sand, 3/4"-1". My tanks dimensions are 36"x 24" for the bottom. Does anyone know how many pounds of sand I will need?

Thanks in advance!