ok I just need some confirmation on this, so say the key signature on some sheet music is 4 four sharps, this means it's in the scale E major since since the E ionian scale has 4 sharp notes (here's were i need clarification) if it's in the key of e major then you sharp any note in the song that is sharped in the e major scale. is this right?

Don't think in "E Ionian scale" since you really only need to think of it at "E major scale". And yes, any note sharped in the E major scale (F, C, G, D) will be automatically sharped in whatever piece you're playing, unless otherwise noted.

you got it right. If a pitch is sharp or flat in the key signature, it's played that way throughout the piece.

...unless you come across an accidental (a sharp or flat next to a specific note.) Accidentals alter the pitch from the key signature until the next bar line, then every note goes back to they key of the piece.

http://en.wikipedia.org/wiki/Accidental_(music)

Don't think in "E Ionian scale" since you really only need to think of it at "E major scale". And yes, any note sharped in the E major scale (F, C, G, D) will be automatically sharped in whatever piece you're playing, unless otherwise noted.

Ionian scale = major scale