How hard is it to get the Virgin train tickets to Liverpool from London? The price seems quite reasonable at 20 BSP each way compared to the day tours to see the Beatles exhibits which run about $200 pp. even though you have to pay for the sights once you get to Liverpool.
If you want tickets that cheap you need to book online as soon as you see them as they sell out fast. (Generally they go on sale three months ahead.) Be warned that those tickets are strictly limited to the train you pick when you book - if you miss it you will have to buy a new ticket at a much higher fare.