Here's an online topographic map of the Lake Alpine area from Caltopo.com.
Purple dashes are suggested mountain bike routes (open to hikers too, and cars for the forest roads), red lines are some suggested hiking routes. Note that if you zoom in there are additional trails as mapped by the Forest Service. Please note that some of these trails may be poorly maintained or hard to follow, though. For instance we had a hard time following the Emigrant Trail from Bear Valley to the south side of Lake Alpine when tried in the spring. Most trails are sparsely marked in the Sierras, so if you venture far from the road it's best to have a good map with you.
