Peteboy,
There are many decent sportsbook affiliate programs out there to try… but if you want to invest in a sportsbook think carefully as there are many out there strugling to survive in the current climate. Also sportsbooks requires a huge CS department and the more languages you do it in means the more CS staff you require and overheads will be greater. It is not as simple as just building a website in a different language as you actually need to service the players. A good example is BetonSports who has 1,300 staff who work in their main Costa Rican office.
IGW Software
I suggest include my old favorite IGW Software who currently is the software behind VIPSports, Gameday, Sirbet, WSSBSport, FairDealSports, FiveCardCharlie and a few others. They charge a set up fee and and monthly charge as well as % of book wins.
IG-L
IG Ludorum are very big in the industry and is the software behind many fine books including NASA. Their setup fee is reasonably and like IGW charge monthly handling fees and % of net win.
ACTION SPORTSBOOK INTERNATIONAL (ASI EXTENSIONS)
ASI accounts for a good chunk of the online sportsbook market. All things considered, ASI’s clients rank among the biggest in the industry, among them Pinnacle, Olympic Sports, Millennium, Grand Central, Rio International and First Fidelity. ASI is cheaper than the other softwares out there but it lacks technical support.
My preference is IGW, but I hope this helps.