Minimum Item Level for First MoP Dungeons
You need an average item level of at least 358 to queue for the Normal mode of Temple of the Jade Serpent. In general, questing through a given zone should amply provide the item level you need to queue for that zone's dungeon.

358 isnt a biggie? ok not at least for us for new lvleded 85's it can be abit annoying.

Do we need to find the entrance before we can queue for the dungeon again?

You are going to have the ilvl from questing.

Hopefully yes.

Questing sucks, and you don't actually have the ilvl from questing since the zone begins at the same level as the dungeon, e.g going from wrath to cata you need ilvl 289 for the first dungeons but lvl 79 wrath quests drop ilvl 200 gear.

there for we got the AH to buy some 80 gear n such so ye it can end expensive for some just to get fast into dungs at 85 > 86

The Jade Forest - Quests most of the rewards are 372 or 384 so you can have the 358 as soon as you complete some of them. You can also have some easy 364 items from Cata (like the Thrall quest), BoE and rep gear to help you boost your ilvl to 358.
I think it will be much more easy that it was from WotLK to Cata.

I still think its a bit of a failing, obviously i don't mind questing on my first toon, but considering you have to the same area every time it can start to grind.

The ilvl calculation doesn't help either, just 1 bad slot (like a trinket) can skew your average ilvl hugely. And ofcourse everyone solves it by stashing items in their bags.

It's even worse when i you have to carry around a plate helm because your BoA helm has an ivl of 1. I roll on item drops in dungeons just for ilvl.

fair points