Look online for a code generator! People do the same with Xbox Live Microsoft points, online bots that add a variable increment once a code is entered immediately etcetera etcetera etcetera... Google one for DSi Ware points but take caution that many code generators can come from unreliable sources. They are legal because they are paid through ads, revenue and several other payment methods.
Dude i looked "EVERYWHERE". No gens bro. No gens. Can't someone just offer one for all and I repeat for all operating systems. I get so mad there is none for linux. Why only windows!?