Train Travel in England

John - Here is a web site for you to review
nationalexpresseastcoast.com. With early March being 2 weeks away most of the discount fares may be gone.

If you don't care how much you have to pay for a walk-up ticket (as much as £63 for London-Bath, £70 for Bath-Penzance, £119.50 for Penzance-London, and £74.50 for Bristol-London), then it's not important to book in advance. If you can commit to specific departure times on specific dates, book now on the site Joel gave and you may still be able to get discount fares. If you need flexibility in your travel dates but don't want to pay the high fares for last-minute tickets, then a BritRail England Flexipass covering 4 days in 2 months might be a good choice. It costs $265 US (£184 at today's exchange rate). Click on the Railpasses tab at the top of the page you're reading now for more information.

Thanks, guys. I think the pass is a good idea for the flexibility.

The best deals are always prebooked.
Also try the megatrain website, they have fares to Bath from £6. Its a very limited timetable/number of seats though. They alsio run services to Bristol and exeter from about £10 per journey.
A website I've just found, is railsaver.co.uk, and seems better than most others as if checks for split-ticketing with multiple searches.

Assuming you get a cheap ticket to Bath, theres a freedom Of the South West railrover ticket giving 3 days unlimited rail travel over a 7 day period for£70

Trains are expensive in Britain. Check out busses as an alternative. Since the distances are short you don't lose much time but you save a lot.