At what level do Warriors start having good aggro?

I initially started leveling up both a warrior and a shadow knight (in their 30's on both). The warriors aggro feels so terrible to try to build up and the shadow knights just feels about 10 times better. I have the lvl 20 provoke for the warrior but doesn't feel like it helps much.

Is there certain new abilities that warriors get at a future level that really make a big aggro difference?

In the old times, we relied on dual wield (DPS) and the odd proc for agro and the raid having had to pay attention to overagro-ing was common. You might want to check the relevant procs and generally fast weapons (SBoZ for example which i take it you have since it's "the" twink weapon).
At your level though, provided you are on a live server, don't worry - take a tank merc and level up.

A knight has his spells to help with agro, but that "advantage" is mitigated and nullified as you level. (especially the closer you come to 101 and over).

Until you haven't reach levels that give you 3 aggro disc lines, that we got upgraded each expansion level. It starts at lvl 80. For each 5 level, we get one hate disc line, one hate over time disc line, and one AE hate spell line. Also, once you have access to AA that reduce recast time of the 2 single target aggro lines, you will be able to click them more often and will improve very much your aggro. I don't remember when you have access to these AA lines, but first ranks must be around 85 ish lvl or so.

Dual wield weapon's with low delay's and stun or rune proc's

Gnoll Hide Lariat
http://everquest.allakhazam.com/db/item.html?item=5317;source=lucy

Silver-Petaled club
http://everquest.allakhazam.com/db/item.html?item=71397;source=lucy

And also get the cheap stun weapon augs or self heal augs.
http://everquest.allakhazam.com/db/item.html?item=51724;source=lucy

You won't be able to beat the SHD for agro, but you should do fine.

I like to pull with Warrior using the provoke line. Has decent range and later on it's quick refresh. Gets that agro generating right from the start'=)

To also answer your question yes, warriors get plenty for AE agro. Wade into Battle, Harmonious Expanse, your Stormwheel Blades line ( starts in 70's I think and get every 5 lvls, ae atk with fast refresh.), Area Taunt AA, Rampage AA. Probably more I forgot.