Grappling...

[ZansForCans]

Sorry, missed Hyp's post while taking forever to write this... I agree much more verbosely (as usual) below

Re-reading the grappling section once again, I didn't find where it states you need to use an attack action to maintain the grapple and/or pin.

You don't do anything to maintain a grapple. You or your opponent must take the "Escape from Grapple" grapple action to leave the grapple, which is done in place of making an attack (i.e. it burns one of your iteratives).

What I do see are actions available after the grapple is joined, and all of those specify if the action is made in place of an attack.

Yup.

Once you have your opponent pinned you can do a number of things as suggested, though it doesn't say what type of actions these are.

Sure it does:

"If You’re Pinning an Opponent

You can attempt to damage your opponent with an opposed grapple check, you can attempt to use your opponent’s weapon against him, or you can attempt to move the grapple (all described above)."

Since they are all described above, you can see that every one of those is in place of an attack and again burns one of your iteratives.

However, the 1st level fighter pinning a wizard can deal out damage or take one of the other options.

No she can't. As you quoted above, "Pin" is in place of an attack. "Damage Your Opponent" is also in place of an attack. A 1st level fighter (not hasted) doesn't normally have two attacks when taking the full attack action.

The pin lasts for one round. At the start of the fighter's next turn, the wizard is not pinned. The fighter can choose to pin again for another round. It burns another attack.

 

[MarauderX]

...
Sure it does:...

Right, right, but what I am looking for is the way that it is stated in the above portion under grapple. It doesn't state "(in place of an attack)" as directly as the pre-pin grappling actions.

And yes, pin only lasts for 1 round, thanks.

 

[ZansForCans]

Right, right, but what I am looking for is the way that it is stated in the above portion under grapple. It doesn't state "(in place of an attack)" as directly as the pre-pin grappling actions.

I take the "(all described above)" as meaning you refer to the exact definitions and rules described in that section.