i got mine 2 months ago for £14 return on eastcoast site, can't put a link up as im on mi mobile blower, just Google eastcoast trains,
The cheap tickets are the first to go so you will be lucky. You have to get in there as soon as they're out. I just got £11 return from Donny to Kings Cross on the day we play Watford. Not gunna the match though. www.eastcoast.co.uk
Just done a quick one for you: Out on the 6.35am train back at 7.20pm £48.75, thats the cheapest with decent times. You can come back on the 10 train for a tenner cheaper.
Ours were £20 return (Donny-Kings Cross). I think the even cheaper ones, e.g. £14, were based on big group booking discount of 1/3 off for 8 or more travellers yeah? We got ours in first couple of days of release to get them cheap. 08:53 out, 19:30 back. Now about £50 I hear.
Might not be the best journey but look at National Express coaches if you're not too bothered about getting a drink while travelling. I found Glasgow - London return fopr £40, must be cheaper from Yorkshire!