When should I start worrying about gear?

[lujate]

For example, my L10 Gladiator is still using the starter sword.

[jabbywocks]

You should be getting better armor and weapons if you're following the main story quests and also most side quests and class specific quests give equips.

[Asdamine]

Do not worry too much about it. You will get most of your gear from dungeons. No need to buy gear from the market or take the gear from quests (always take the coins, because those gear are cheaper than the coins you get from those quests).

Update your gear as you get gear from each level of dungeons, starting from lv15.

At level 50, that's the only time you will majorly spend your money on gear to update every weapon(s), accessories, belt etc to lv50 to prepare yourself from en-game dungeons farm.

[JagerForrester]

The important thing you will be spending money on is transportation (chocobos, teleports, ferry rides, airship rides). You can get by with just getting gear from the story quests, class quests, and the miscellaneous quests along the way. This will take you all the way to 50. Keep the "Recommendations" window open to stay alert of any quests available to you in the vicinity.

[GinTama]

update your gear before going into a dungeon

[Toranja]

You start getting killed would be a good indicator.

[Urthdigger]

I'd say a good rule of thumb is to upgrade your gear every 5 levels. If you do your class quests, they will upgrade the weapon for you. While you CAN just use gear from dungeons, you're likely not going to do so well in the level 15 dungeons in level 1 gear. That argument also assumes you're regularly running dungeons. If you're running FATEs to level like 99.9% of the population, you're not getting gear as you level.

So, yeah. Upgrade every 5 levels or so.

[Pinworms]

You should worry about gear before you step foot into ANY dungeon.

[lujate]

Quests and FATEs haven't been a problem (except for the occasional, "whoops, that was a really bad idea!").

I am almost ready for the first dungeon, so where's the best place to get gear, NPC's, AH? I already did the main quests on my Conjurer up thru like L16, so that's not an option.

[Lemon8or]

I'd say you can get by with relatively not best gear you can equip until Brayflox. That was the first dungeon that mobs do increased damage from my experience.