Are the bulb plastic and do they give off a warm light?
Bulbs are glass and yes, it's a warm light (not that ice blueish white) .Do this item has an end to end connection to connect another string light?
Yes, the light has an end to end connection to contact another sting light.
How long is the lead from the socket to the first bulb?
Plug to 1st socket is 32"
If one bulb burns out do the rest stay lit?
Yes, if the one didn’t light up obviously and all the other bulbs still come on.