My eighth level character going ninth level is starting at first level war blade. He would get one stance and 3 maneuvers at up to 3rd level. Could I take absolute steel stance and iron heart surge both having prerequisites one iron heart maneuver at the beginning of this level? In other words, can a stance and a maneuver at the beginning of the class level be each other's prerequisites?
Tome of Battle pg. 44, under Prerequisite:
you must meet a certain set of requirements to be able to choose that maneuver as one you know. [...] Some of the more powerful maneuvers require you to learn one or more other maneuvers in the same discipline before they can be selected.
So you cannot choose iron heart surge unless you already know an Iron Heart maneuver, nor can you choose absolute steel stance without knowing an Iron Heart maneuver first. Since you cannot choose either, one cannot be used to meet the prerequisite of the other—you need to actually have one first before you can meet the prerequisite of either, which you can’t do.
However, you can choose one or both of these maneuvers if you also choose another Iron Heart maneuver at 1st level. For example, you could choose steel wind as one of your three maneuvers known at 1st, and then you would be able to choose iron heart surge as one of your other maneuvers and absolute steel stance as your stance.
Furthermore, if you get to warblade 4th and get to swap a maneuver known for some other maneuver, you could choose in that case to swap steel wind for something not from Iron Heart—or for another Iron Heart maneuver that had requirements. Since at that point you already have both iron heart surge and absolute steel stance, even if you lose steel wind you still meet the prerequisite of one Iron Heart maneuver for each of them—in fact, you actually have two Iron Heart maneuvers. So you could swap steel wind for mithral tornado, which requires two Iron Heart maneuvers, and end up with iron heart surge, mithral tornado, and absolute steel stance all functioning. The replacement mechanic can also wind up with you in other kinds of otherwise-impossible situations, such as having iron heart surge as your only Iron Heart maneuver—you would have had to have some other Iron Heart maneuver at some point, but you could trade that away and iron heart surge can meet its own prerequisite.