So when playing solo queue it seems most often the role of an initiator/tank/somebody with CC and the ability to take a hit is often left unfilled. Other than that, it's a 50/50 if we need AD or AP. While if I want an AP tank, I can pick, well, just about any tank, however with an AD, I don't really know what to go for. What functions effectively as an AD tank? As in abilities do AD damage, not magic primarily.

i don't even know what the hell you're talking about... malphite? mundo? voli? .... what do you want to know... engage? take tower hits? BE A TANK?? xD

What are some AD tanks?

I think almost all tanks are AP, yes. I don't think that's gonna change. But it doesn't mean that they don't do any AD damage.

Ever heard of the auto attack?

Irelia

AD tanks don't exist because of Atma's. You think Tanky DPS is a hassle? DPSy tanks would be even worse.

I like Voli quite a lot. You won't really be buying AD items, but with frenzy's bonus to IAS combined with his charge-flip and aoe slow, he can be a fight changer for sure.

AD Sion can build pretty **** tanky too, with atmogs etc.

Probably my top two picks.

TRYNDAMOREEEEEEEEEEEEEEEEEEE!!!!!111!!!!!1!one

Well Yorick is good with AD and tank runes but in game you build him with health and mana items, though he is more of a utility with sustain than an actual tank.

First off, Jarvan IV.

Skill up Blitz' W and E first and he'll do a decent amount of physical damage. Works well with Triforce + tanky or with manamune too for more AD.

Ali's ult actually gives a large amount of AD, but you would probably have to build some attack speed from something else to notice much damage out of it.

Beyond that you have to start getting more lenient in what you consider a tank. I bet with some CDR and a pretty modest amount of AS you could get quite a bit of CC out of xin zhao.