Well, I guess back in the day shoegaze and it's musical sister dream pop were just feeble imitations of a few great artists.
My Bloody Valentine, Cocteau Twins and whatnot.
Shoegaze usually consisted of heavily effectualized guitars...the use of tons of reverb, chorus, and delay to make a self describes "wall of sound"
All of this, in my opinion, being a big imitation of Kevin Shields and My Bloody Valentine's "Loveless" album, which seemed to use these same elements, but actually didn't. It was quite an album, actually...I think it was genius...
As I remember the beginnings and roots and whatnot, it pretty much died out in the nineties, leaving behind some good recordings here and there sans the legendary ones.

And now...its back I guess, with a more nature-oriented, dark, and mysterious outlook rather than the old hipster/indie type thing.

Here are some noteable artists, songs and videos(new and old) for shoegaze and dreampop.

My Bloody Valentine- Only Shallow

Slowdive- Alison

Tearwave- Dream Bliss

Lycia- Estrella

Autumn's Grey Solace(my overall favorite band) myspace music

Love Spirals Downwards- Myspace music