http://forum.bodybuilding.com/showthread.php?t=998224
do this. heavy weight lifting gets you muscle very fast. pushups, etc. not so much.
big problem is going to be your diet. name a muscular vegetarian. exactly. it's going to be very tough getting enough calories and protein as a vegetarian. if you really want to get muscle, i would consider reevaluating being a vegetarian.
actually if going to the gym is really a no-no, consider buying an adjustable kettlebell. good all in one workout device.