Just started looking for value........starting with pre-tournament offers :
Sky bet - £10 on the winner gets you a £3 bet every time they win (incl pens etc)
Stan James - £20 on top goalscorer gets £5 bet every time he scores.
Betfair - £25 on tournament winner gets £5 every time they win.
Hills - £10 on England gives £5 every time they win.