Depends really. My initial reaction was, "no, it should be, 'it sounds like a little corner of heaven there" because "it sounds" suggests that you're talking about something that's not currently with you. BUT Say you went on holiday, and you were in the beautiful place, and in that beautiful place you were reading about all the things it was famous for, and visited for, you could then, feasibly say, "It sounds like a little corner of heaven here". So. Yes it works, but only depending on the context.

It really depends on context as C.M. was saying, but if you want a colloquial phrase that sounds good for a general context, I would go with Tim's suggested phrasing.

I've never heard a little corner or heaven used. I understood it, but I don't think it's correct. I think it should be "piece" of heaven. "It seems like a little piece of heaven here."