Mass outdoors has lake maps with some depths on them,they also shows access points.
The best way to find the ramp is google Lake Boone and find Daws lot.It's off of rt.20 and right at the Stowe town line.It's at the southern end of the lake.
Rt 128 to rt 20 w,to rt 27 n.Hudson rd to sudbury rd.at intersection of sudbury and state rd stay right launch will be on the left.It's a downhill unpaved access but the ground is pretty solid there.If you have a gps enter intersection of state rd. and sudbury rd.sudury ma.
not every lake is on there, they might have it one of those local area fishing books that you can pick up at some Dick's or I've seen them at Cabela's. Different lakes, depths, species, access points for states or regions.