Bang have the Lost Boxsets at decent prices, compared with elsewhere.
HMV are the cheapest, by a fair bit for Season 4.
Links all below.
Season 1 is the "go to deal" link
From J.J. Abrams, the creator of Alias, comes an action-packed adventure that will bring out the very best and the very worst in the people who are lost on a faraway desert island.
Out of the blackness, the first thing Jack (Matthew Fox) senses is pain. Then burning sun. A bamboo forest. Smoke. Screams. With a rush comes the horrible awareness that the plane he was on tore apart in mid-air and crashed on a Pacific island. From there it's a blur, as his doctor's instinct kicks in: people need his help. Stripped of everything, the 48 survivors scavenge what they can from the plane for their survival. Some panic. Some pin their hopes on rescue. A few find inner-strength they never knew they had.
Kate (Evangeline Lilly), with no medical training, suddenly finds herself suturing the doctor's wounds. Hurley (Jorge Garcia) - a man with a warm sense of humour despite the desperate situation - does his best to keep his cool as he helps those around him to survive. Charlie (Dominic Monaghan) is a faded rock star who harbours a painful secret. Sayid (Naveen Andrews) is a Middle Eastern man and former member of the Elite Republican Guard, who must wrestle with the racial profiling directed at him by some of his fellow survivors. Jin (Daniel Dae Kim) and Sun (Kim Yun-jin) are a Korean couple whose traditions, values and language are foreign and thus causes much to get lost in the translation. Sawyer (Josh Holloway) has an air of danger surrounding him, and his intense sense of mistrust for everyone around him could prove to be fatal to his fellow castaways. Michael (Harold Perrineau) has just gained custody of his nine-year-old son, Walt (Malcolm David Kelley), after the death of his ex-wife - they are a father and son who don't even know each other. Locke (Terry O'Quinn) is a mysterious man who keeps to himself, and who harbours a deeper connection to the island than any of the others. And self-centered Shannon (Maggie Grace) - who actually gives herself a pedicure amid the chaos - and her estranged controlling brother, Boone (Ian Somerhalder) - constantly bicker and must learn to get along if they are to survive.
Pilot (Part 1)
Pilot (Part 2)
House Of The Rising Sun
Raised By Another
All The Best Cowboys Have Daddy Issues
Whatever The Case May Be
Hearts And Minds
Deus Ex Machina
Do No Harm
The Greater Good (aka Sides)
Born To Run
Exodus (Part 1)
Exodus (Part 2)
'The Essential Lost' featurette
'The Genesis Of Lost' featurette
'Designing A Disaster' featurette
'Before They Were Lost' featurette
'Welcome To Oahu: The Making Of The Pilot' featurette
'The Art Of Matthew Fox' featurette
'Lost' at Comicon
'Lost' on location Audio commentary on the 'Hearts and Minds' episode from stars Maggie Grace & Ian Sommerhalder and writers Carlton Cuse & Javier,
Grillo-Marxuach 'On Set With Jimmy Kimmel': the American comedian and show host goes behind the scenes and meets members of the cast and crew
'Backstage With Driveshaft': a great insight into the development of Charlie, the band Driveshaft and who wrote the song that features through out the series
'At The Airport - A Feature With Claire': an unseen flashback of Claire checking in at the airport before the flight
'At The Airport - A Feature With Sayid': an unseen flashback of Sayid checking in at the airport before the flight
Live from the Museum of Television and Radio
*Season 1 also available at Amazon for this price