Welcome to the forum willzB
I think this topic would belong in the "I'm New" section

Well about the site thing if you want to start from the ground up i suggest you look around for some starter tricks on the diabolotricks site (
http://www.diabolotricks.com) And then move on to more complex tricks
And about the 1D 2D and 3D it stands for 1 Diabolo, 2 Diabolos, 3 Diabolos
It's terms in juggling to make everyone's life easyer
Hope this helped and if you have anymore questions i'm pretty sure the people at diabolo.ca are really helpfull
I found them really helpfull
And remember diaboloing is for fun not hard work

~Adam