I second Ruben's recommendation of Berkhof's little concise book (it's only 166 pages).
For further reading on hermeneutics, I'd highly recommend Foundations of Contemporary Interpretation edited by Moises Silva. This book doesn't really lay the foundations of hermeneutics as a science (or art, as the case may be), but builds on them; whereas Berkhof provides the basic rules which are essential to contextual exegesis.
Sure - Samuel already mentioned it: Foundations of Contemporary Interpretation. But it doesn't start at the very beginning, the name notwithstanding. There are many other books, including special treatments of particular points. But I have often felt that looking at how a great interpreter (like Thomas Goodwin) gets from his text to his conclusion is actually more illuminating than the theoretical manuals.