I agree with the others, a scrap yard is the place to get your steel. I
went to my local yard and asked for a hunk of steel sheet and tube
and/or angle suitable for making a small welding table. I was in luck -
someone had recently scrapped two complete welding tables! I took the
one with a 2ft x 3t x 1/2in top ($20), which was just the size I wanted to
build. The other table was enormous, bigger than 4ft x 8ft, way too
big for my work space.