@shorty42,
I would give him one of those little boxes of candy hearts that have the little messages on them, like: crazy4u .
And then I'd buy something else, like a cd or something and first I'd give him the little candy hearts sort of like a fun little something you just picked up off hand and then if he didn't have anything for you - just leave it at that and keep the cd - but if he did have a present for you and you wanted to reciprocate with something bigger - you'd be prepared.
Or you could just say, 'I wanted to get this for you because I saw it and I thought you'd like it', and give him something whether he gives you anything or not.
But either way - I'd give him the candy hearts - those are always good for a laugh.