Hi Justin
As you mentioned you like Coupling, I'd try Joking Apart (though the only place to get it from is www.replaydvd.co.uk!) It's written by the same guy and was the predecessor to the aforementioned series. I think it's superior, too.
Nathan Barley is great too, though a lot of people didn't enjoy it so much over here. I think, as you liked the silliness of Black Books and Father Ted you might enjoy it.
If you like *really* surreal, try The Mighty Boosh. It takes a couple of episodes to get into, but as soon as you start 'getting' the humour/banter, it becomes a really excellent show.
15 Storeys High is very good too, though quite bleak in a lot of it. Also, I'd recommend the recent Respectable, about a man who becomes good friends with a prostitute. It was very clever, funny and well done.
Enjoy
Dan