"White" is kind of a generic answer. What you want is a friable aluminum oxide wheel in either 80 or 120 grit. Some are blue, some are white, pink, etc.
You will definitely get what you pay for. The $20 white ones will do the job but a $50 Norton 3X (blue) will do the job much better and will probably be better balanced out of the box. It'll last a lot longer too.
As far as grinder jigs, the OneWay Mfg. Wolverine is pretty much the benchmark. It is a great system and really isn't all that expensive. PSI makes a slightly cheaper version. I've seen people make similar jigs out of wood or metal, and then use shop made jigs that mimic the Wolverine's vari-grind jig. Not my thing but it can be done successfully.
Don't worry about the speed of your grinder. Some people will say you need a slow speed grinder, which you do not. Faster grinders just remove more metal, that's all. You cannot ruin the temper of HSS tools on a grinder despite the occasional person that insists that you can.