where frameid is the id associated with the iframe.
nearly. frameid will return a reference to the IFRAME or FRAME element not the actual frame's window.
I still prefer the frames.document.getElementsByTagName("*") approach though.
If for some reason one wanted to get every element in every frame combined into a single array of references, one could loop through the frames using frames.length and one by one checking if each frame contains any other frames then one by one executing document.getElementsByTagName("*") on each of the frames then storing the references to each element contained within each frame.