So where can you watch comet ISON during perihelion??? There are many sites where you can watch the data roll in. Here are the ones I know about.
SDO has a dedicated page, it will update every 5 min with new data:
http://cometison.gsfc.nasa.gov/
Here is a link to the SOHO ISON page. It is not as dynamic as the SDO one, but they have now provided links to the latest data.
http://sohowww.nascom.nasa.gov/hotshots/index.html/
Here is the STEREO page about ISON. Sadly though the page provides no links to live data.
http://stereo-ssc.nascom.nasa.gov/comet_ison/
But, here is that link. Here you can select which instrument you want to view, then the date. You will then be given all the available images for the selected day.
http://secchi.nrl.navy.mil/sccimages/