What specs do I need on a net-book to stream non-hd english subbed anime?

Specs don't make any difference.

As long as you have 2gb of RAM and a decent processor you aren't that heavily limited with things like that.

All you probably need is Flash Player which is free and a wireless connection to the internet and/or a broadband card.

It depends on the quality of the hd stream. I would only consider buying a netbook with an nvidia ion for intel or a 13" dual core neo from amd. Graphics are only going to get better and more demanding, get a netbook to handle some of what to expect in the future instead of just the present.

Episodes with this quality don't really require and specific features to play.

any really beause all you need is a plug in of course internet connection is a whole different story