So say I'm using a lvl 15 axe with 99-119 dmg and 83% ee

Would the same axe but lvl 45 hit harder?

I'm confused as to how the level of the item effects damage when it shows to be nearly the same.

http://ladderslasher.d2jsp.org/index.php?g=3

Yes. Each tier has a base damage. Progressively higher as it goes up a tier. The EE is a multiplier of that base damage.

A plain white lvl 45 axe would be better than the lvl 15 83ee

Sweet okay thanks. Spent 50fg for one and I can't tell much of a diff I still kill slow and spend most of my time healing in town

Pm me if you have any questions, ladder slasher is definitely a game where you need to invest into your gear If you don't just buy fg I suggest also playing another game to save up fg for item upgrades, I may have some things I could sell you cheap but if you plan on climbing etc you'll need a lot of stuff.