I made a deck today at home without any special equipment. It doesn't look the greatest, but it's more than functional. I just can't do the welding at home. Buy an angle grinder and try it.
I would never try to "carve" a one piece deck out of aluminum. How would you ream/face the head tube anyways? If you want to build a deck, you could try making a 3-bolt system with the stock razor head tube. I would use 1/8" 6061 plate and 1x1x.125 6061 tubing. I'm sure you could find this metal locally. I've been riding mine since early spring, but I just refinished it over the weekend; my brake was busted, so I made a flex brake...