Augustiner is a great biergarten just be careful on the Edelstoff, stronger than the normal Augustiner that they sell there!
Good chance of the weather being shitty this time of year though, and probably will be very quiet as the locals will be at the fest!
You can get to the Oktberfest in about 10mins walk from there, come out of the Augustiner and cross the bridge.
There will be no problem getting in tents at that time, and later in the afternoon they will be rocking!
The HB tent has a unreserved standing area in the centre of it as well.
It's well worth seeing if your only here for the day!
Other than that, loads of bierkellers, Lowenbraukeller, Knockerberg, HBhaus, HBkeller etc and loads of good pubs augustiner am dom and andechs am dom are next to kilians in Marinplatz.
Well be great to see loads of blues in town anyway!