IE in Metro mode does not support any plug-ins or add-ons, except Flash, and even then that was initially for select web site until demand made Microsoft change that.That doesn't work for IE in Metro mode, unfortunately.
The decision for that was for security reasons.
This is the best you can get. And as mentioned IE Metro doesn't support add-ons. You need to make your own web browser.IE's adblock doesn't seem as robust as FF/Chrome though. ABP for IE (was called Simple Adblock?) can only use one filter list at a time, less configurable, and I think enforces "acceptable ads" (which can be good or bad depending on your point of view). And as mentioned, not available in IE Metro. It also seems to hang up desktop IE more often than FF/Chrome. For example, Yahoo front page seems stuck with perpetual spinning wheel using ABP for IE.