Well, so at the time the Etruria (their land) was reduced to the current region of Tuscany (one of the most beautiful regions of italy), because of the gaul invasion in northern italy of 4th century b.c (at which survived just liguria and veneto), they lost all of their commercial cities in the Po Valley such as Spina (where they had the first contact with greek culture on the adriatic sea) and Felsina (the modern-day Bologna, city where i live), and it had a great repercussion on their economy, and at south they have lost their commercial stronghold of Cuma, taken by the greeks of Syracusae.
And in the sea that still bear their name, the Thyrrenian, once entirely controlled by them arrived the strong competition of the Poeni (Carthaginians), so, as if they always been in the previous centuries a commercial empire, losing control on both seas has significantly started their decadence.
Rome too already attacked and beated them in the battle of lake Vadimo (309 a.c), taking advantage of the fact the Etruscans were just the shadow of their glorious power.
So, as i say they always endorsed commerce (using barter more than money) instead of military power (they never really occupied or subjugated any other italic culture), they were a peaceful people, with strong traditions and much superstitious on their beliefs, but even ingenious, they created the first architectural arch and the gladiators games, so you see how much rome owe to them
So this was the situtation at the time and a bit of their order, ask anything else you want to know about, weapons, equipments, etc.
This is a drawing i have made of how their hoplite should have appeared:
http://b4ld3r.deviantart.com/art/Etruscan-hoplite-268336281
(in a certain moment of history they also used as second weapon (first was the lance) a double sided axe)
Even if they had a strong equestrian tradition, and used much chariots, even for their general guard