How to use 面 ？？？

[kentaku_sama]

I know it means face or　Surface　Oｒ something like that but how is this actually used? I came across it recently as I was reading Ja.wikipedia: また、内部機構の面からは打楽器と弦楽器の特徴も併せ持った打弦楽器に分類される. I figure it means something like aspect due to the context but I want to be sure and I don't know how to pronounce it either other that めん。

[Harisenbon]

In this case, yes, it does mean aspect.
面 has a lot of meaning when translated into english, but it easiest to just think of it as being a "side" of something.

面 【めん】 (n) (1) face; (2) mask; face guard; (3) {MA} (in kendo) striking the head; (4) surface (esp. a geometrical surface); (5) page; (n,suf) (6) aspect; facet; side; (7) chamfer; (ctr) (8) counter for broad, flat objects, levels or stages, e.g. in a video game; (P)

in most cases it's read めん、but there is also a noun suffix which is read づら, and means "to look like"

[kentaku_sama]

どうも！！　今「面」が知るよ。

[Ben Bullock]

I know it means face or　Surface　Oｒ something like that but how is this actually used? I came across it recently as I was reading Ja.wikipedia: また、内部機構の面からは打楽器と弦楽器の特徴も併せ持った打弦楽器に分類される. I figure it means something like aspect due to the context but I want to be sure and I don't know how to pronounce it either other that めん。

Your guess is OK here. In the above it's めん rather than つら. 面 has two common pronunciations, めん meaning "surface" or つら meaning "face".

For example, 面積 (menseki) means "area" but 泣き面 (nakitsura) means "a crying face" and it's used in the common phrase 泣き面に蜂 (nakitsura ni hachi) which means something like "adding insult to injury". However, sometimes there are phrases like 面食い which is pronounced "menkui" but means someone who is "attracted by physical looks only", as it says in WWWJDIC.

So it's a good idea to learn the words in context.