The reason you can't find much info about the wireless peripherals for pc gaming is cuz most people still prefer hardwired keyboards/mice to ensure that there is absolutely no loss of data and faster response rates..
Personally, i would stick with wired but you want a HTPC! what a dilemma!
I don't know much about wireless gaming peripherals.. I know logitech has the g7 mouse but don't know much about other gaming gear that's wireless..
Someone help this guy!