Pads: You have one option, which is Mad Katz' Street Fighter IV pad. It works pretty good and is what I have use when I want to play 360 fighters with a pad. It's got six buttons on the face and that alone makes it 10 times better than any other pad you can get.
Sticks: Depends on the quality you want. The better the stick, the higher the price! Hori is generally regarded as kinda shitty, but if you can get one cheap enough, it's fine to start out with.
I want to swtich to a stick, but I am still waiting to see if someone will ever make a universal stick that is compatible with all three systems. Really it's just a problem for the 360, since you can get PS2 controller adaptors for PS3 and Wii (Game Cube).
Also remember that you can use 360 controllers on PC, so get to emulatin' and try out some more fighters! KOF '98 Ultimate Match is, in my opinion, one of the best fighters ever made. And yes, it tops Garou. Not in animation, but in everything else.