This work is considered quite reliable and it's an accredited source for what concerns Japanese heraldry.
Here I found the banners that were supposed to belong to Nobunaga's army:
The first and third item are recognized as horo (母衣), respectived of the black (黒母衣衆) and red (赤母衣衆) units.
The second item is the uma-jirushi, a standard coming in varied shapes that pin-pointed the location of the daimyo on the battlefield. Nobunaga's rappresents a golden umbrella, here.
And finally, the last item is a nobori, which is nothing but what we called a banner 'til now.
As you can see, it's not decorated by the Oda kamon, but by the eiraku tsuho coin, one of Nobunaga's personal symbols.
I found a similar reference on this painting of the Battle of Nagashino, preserved in the museum of Nakatsu Castle (中津城):
You can spot Nobunaga at the end of the marching group, mounted on horse.
He's preceeded by a tsukaiban sporting a red horo, and you see again the coin on his banners.
Here are different uma-jirushi, though: instead of a golden umbrella, you can spot black feathers decorating them.
In this painting we can also see the exhibition of the "lord's helmet": besides the practical reason, the bearer of the helmet was considered as the bearer of an uma-jirushi.
For further pics, I suggest you to take a peek at this page; you can see further versions of the same banner, coming from other paintings or prints.
The picture contains also a depiction of the Oda clan's sashimono, which is very curious, as it doesn't contain any kamon again.
At this point I wondered about what the Oda clan sported on their nobori before Nobunaga's rise to power --And I couldn't find anything. Apparently whatever was of the Oda clan before Nobunaga has been removed from the collective memory..?
The only nobori left related to the Oda and sporting the kamon that I could find, is that of Nobunaga's son Nobukatsu, that apparently used a multicoloured version of it.
An example can be found at the Rakusan'en garden in Gunma Prefecture:
Picture's source: http://blogs.yahoo.co.jp/pasyatom26ebf2b/30698687.html