How many steps are involved? I wouldn't consider this job for a weekend warrier unless you're very patient and have the proper tools. Tools? Table saw, and sliding compound miter saw(to make one pass on a crosscut) to mention a few.
Chances are you'll need the circular saw as well, depending on how the steps are constructed. This tool will be needed if the underlying steps are "bull nosed" whereas this piece will have to be cut back to accomodate a proper installation.
Though I can't see your situation, I personally feel you'll be better off letting the pro's do it. I can see Diy'ers doing simple square rooms and so forth but stairs? I'd have to say no, as it requires precise cuts against the stair stringers, unless you want unsightly shoemold or quarter round in that area.