VictorChandler.com ... safe British book .. I think they take US customers.
50% cash back on first bet (maximum $75 Rebate, must be bet on an even money bet or underdog: +100, +120, +200, etc.
Victor Chandler CashBack
"Cashback Terms and Conditions
Offer applies to over 18's only.
You must not be an existing Victor Chandler.com, Victor.com, Spinroom or Victor Chandler International telephone betting account holder.
Cashback is limited to one Cashback payment per customer and applies exclusively to the first account opened.
Void bets do not qualify for the cashback offer.
If the first bet contains 3 or less selections, at least one selection must have odds of Evens or better (Odds Against).
Transfer of funds to, or transactions in, 'theSpinRoom.com' On-line Casino DO NOT qualify as a first bet.
Offer applies only to the total stake of your first online bet.
The Cashback will be credited to your account normally within 24 hours of your first bet being settled.
Your debit/credit card must not have been used to deposit funds on any other Victor Chandler International Internet or Telephone betting account.
To qualify for Cashback your first bet must be placed within 30 Days of opening your account.
Your first bet must be placed online via the Victor Chandler website.
Victor Chandler International reserves the right to withhold any cashback payment where the terms of the offer are not fulfilled.
Victor Chandler International reserves the right to withdraw or amend this offer at any time without prior notice.
The 50% Cashback Offer applies to new accounts opened from 00:00 CET on 28th March 2002."