Pasting columns from other sheets into 1 tab

[Covert Wombat]

I would like to have a script where I can paste everything from Column D on a tab called "Product A" onto a new tab called "List", then on the line below the last pasted thing I would like to add a word "Next Product", then after that I would like to paste everything from Column D on a tab called Product B.

I have a few other to add but if I can get those two working then can add the rest I need.

I do have a macro setup where it will do all this, but if I need to change the number of columns I have to go through and recaculate all the row positions in the "List" tab. Looking for something that would be able to just take the count of the rows, then add 1, paste in my word, add one, get count of next tab, paste, then repeat