Some bookmakers is better to use than others when arbing. Pinnacle is a must-have bookmaker for arbers since they will not limit you no matter how much you win. Betting exchanges such as Betfair is also good to use.
Here you find a current, and always up-to-date, list of supported bookmakers.
Remeber to take advantage of the offers and bonuses the bookmakers offer in order to increase your bankroll.