May do you know interesting and new british series? 
Spooks and Sherlock 
Skins, Misfits and the Inbetweeners ^ ^ (depends on what you consider ‘‘new’’ though haha.)
Miranda, The Mongrels and Green Wing
I like ghost whisperer, but is American
Skins, Red Dwarf, Black books, Doctor Who (my favourite one), Father Ted, The IT Crowd, Torchwood
Have you seen the Adventures of Sherlock Holmes series yet? One of my favorites. I have already watched it thrice. Nice and clear british accent. Jeremy Brett is also a fine actor. You can buy DVDs from Amazon or watch some episodes on Youtube. It might be old but it was quite interesting from language point of view.
Two BBC series I really like from the last few years are Life on Mars and Ashes to Ashes. The two series are both connected, Ashes to Ashes is a sequel to Life on Mars but changes its main character. In Life on Mars its main character, a police officer of recent times, gets run over by a car and wakes up in 1973. In Ashes to Ashes a police officer is shot and wakes up in 1981. They are really addicting series and can be very funny.
Just be careful though if you look for DVDs or episodes of Life on Mars as they made an American version of it too which wasn’t as good and got cancelled early.
One of the BBS series that I like the most is Pride and Prejudice (1995). I had just finished the book and found the series very accurate. It has only sis chapter and if you like Victorian period you’ll enjoy it. Mainly if you like Colin Firth. I must confess I fell in love with him, but don’t tell anyone.