Haven't been in the area lately but if you're looking for a reasonable dayhike not too far from Mammoth, check out Glass Mountain. It's east of Mammoth, so likely to have less snow on it. You go across 395 and drive over the road that goes around Lake Crowley. It's about 11,000' and probably about 5 miles round-trip, trailhead to summit and back.
For photos, look at the 2001 Mt. Whitney report under the "highpointing" section of my
WWW site.
Just watch out for the terminally-stupid free-range Black Angus cattle on the road...