Using the values from one cell to identify cells in a matrix

This might be hard to explain...

I want to use excel to identify a matrix based on a variable from a different cell. As an example, i have two cells, C11 and C12, that might have values 3 and 9 in them. I want to therefore find all the values from A3:A9. 3 and 9 may change, so the formula would have to compensate for that.

Is there any way to do this? I've tried saying things like =VALUE("A" & C11: "A" & C12) but i cant get anything to work.