It is best to post code on-line so one can see it. I myself do not like to open attachments.
To put a label on top of multiple plots can be done as follows:

p1 = Plot[Sin[x], {x, -Pi, Pi}];
p2 = Plot[Cos[x], {x, -Pi, Pi}];
p3 = Plot[Tan[x], {x, -Pi, Pi}];
Grid[{
{Row[{"My three plots with one label"}], SpanFromLeft},
{p1, p2, p3}},
Frame -> All, Alignment -> Center]