Remove non-space spaces?

I have a large spreadhsheet with data I've manually copied/pasted from
various sources including web pages.

As I am trying to do things like import to Mysql or even Trim in Excel I
find there are many spaced between words which aren't recognized as such (I
know this because they don't Trim, and or when doing shift-arrow to jump
between words they ignore that space)

Is there some way/function to search for non-space spaces and replace? Is
there some character set they could belong to? I was/am hoping for some type
of advanced Trim function but am doubtful that is going to be that easy.

Right now when I find a 'bad' record I select the character that seems to be
a space, and do a search replace on it with space, but that could take
forever.