Reading books about philosophy of language I came cross a lot of terminology like "metaphysics", "epistemology", "aesthetics", "logical positivist" etc. As I'm a total beginner in this area, I'm looking for a book on philosophy of language that's suited for beginners, i.e. that explains the terminology that's used.
William Lycan's book is easy to read, though perhaps a bit dry. I've used it for an introductory course once. On the other hand, you could also just start by reading original texts. Basic Topics in the Philosophy of Language, edited by Robert Harnish is one of the best collections of seminal articles. It seems to be out of print at the moment, but perhaps you're lucky and spot it in a used book store at a reasonable price.
A great book on terminology would be Papineaus "Philosophical Devices: Proofs, Probabilities, Possibilities, And Sets". It introduces almost everything to get started with philosophy,e.g. the mathematical apparatus, logics, the important distinctions: type/token, use/mention, a priori/a posteriori, analytic/synthetic, necessary/contingent/possible and so on.
You won´t find anything on logical positivism in it, though (i think).
I quite enjoyed Scott Soames' Philosophical Analysis in the Twentieth Century, Volumes 1 and 2. It provides critical introductions to some of the more important philosophy of language writers--from 1900 to the present.
If I were you, I'd start with Alexander Miller's book. (I like it better than the Lycan intro text mentioned in one of the other comments, because I find it easier reading for beginners.)
I'd also get the Martinich & Sosa anthology and read along those primary texts with the Miller.
After that you'd be ready for a more advanced text like Soames's Philosophy of Language book (which is different than his two volume history of analytic philosophy--both are excellent resources though).