Attacking

[Knew45]

At what exact point during the combat phase do attackers tap?

[Millionlittlee]

The first part

[BlackJester]

The first part of the Declare Attackers step.

See Basic Rule Book stickied above.

[Knew45]

So as soon as they are declared as attackers they tap?

[BlackJester]

Yep.  As soon as.

[Knew45]

So as a response to me declaring a attacker could someone use {gideon's lawkeeper}s ability to tap said attacker?

[Gorzo]

So as soon as they are declared as attackers they tap?

Yes. You declare them, they tap, and they are designated as attackers.

You are not able to declare a creature as an attacker, tap it with/for an ability, and still attack with it though. Unless it has vigilance.

[Gorzo]

So as a response to me declaring a attacker could someone use {gideon's lawkeeper}s ability to tap said attacker?

Technically no, once it's attacking it's attacking for good.  The last chance to tap it is during the declare combat phase, just before attacker declaring phasing

[Knew45]

I meant after the creature was declared as an attacker could someone use gideon lawkeepers ability to tap that creature and prevent it from attacking

[Gorzo]

I meant after the creature was declared as an attacker could someone use gideon lawkeepers ability to tap that creature and prevent it from attacking

After it was declared as an attacker no. However often people will skip the "declare combat" step, denying their opponent the chance to do their tap effect when they could, so they declare it as attackers are declared instead.

If this happens, let your opponent know you need to know that combat is being declared before he starts sending attackers. And you should let him re-choose how to attack after you tapped one or more of his guys, since that was supposed to happen before he declared attackers.

[Knew45]

Ok. That clears things up. Thanks.