There are now a couple of sites that show NOTAM plotted on a map. This one makes use of Google mapping, and this one specialises in Ashtams. If you have SkyDemon's planning software running, then that too will display NOTAM once you have a route planned.
But we have to be a bit careful what we wish for. As you can see here, when there are a few NOTAM out there, the whole map becomes covered and there's no easy (or quick) way of making sense of any of it, and although the systems have ways of selecting different bits of data, I still find myself having a quick read through a Narrow Route Brief from the AIS site, just in case there have been any problems in the conversion from text to graphic.
I'm told that things will get easier with digital NOTAM, but they're not here yet.