Not sure if anyone even checks these forums anymore and I know it was asked once long ago in the errata thread but never answered so here goes. In monsters and lairs it lists severed:lich as one of the severed types but never gives the actual template for them. Is there a template for a severed:lich anywhere or am I just maybe blind? Thanks

No, there is no template. It was never done.

Personally, though, I don't see a need for it. There's a severed for each of the elven elements. I can see House Tansiq having a more advanced form of severed of flesh though than what we have.