Hi first time on site. Could some one help clear up the differences between a spinning blank and a casting blank of the same specs. Also the other types of blanks such as steel head ,salmon ect. Or could someone head me to a website that I could get info from on the different blanks.

Curtis,
If ALL the specs are the same there is no difference. Some manufactures/vendors list these in different places for someone looking for a "spinning" or "casting" blank. But any blank can be "cross built" to anything you want it to be as long as the specs meet your requirments.
As far as a website to get info on the different blanks most of the sponsors here list the specs for their blanks or just ask here and someone will surely have some info on the particular blank your interested in.
Hope this helps,
Noel

What Noel said is correct, but I will tweak that a bit. He said "all the specs", but for the recommended line weights, the manufacturers tend to specify a heavier line if they are marketing the blank or rod as a casting model. The exact same blank marketed as a spinning model would likely have a lighter line spec. That spec is more a function of the reel requirements than it is of the blank. And I agree with Noel that you can build any blank either way.