Those may be vintage, but they look quite a bit like these: http://www.restorationhardware.com/catalog/product/product.jsp?productId=prod1677169&categoryId=cat1696068

Those remind me of the lights you can get at Terrain:
http://www.shopterrain.com/outdoor-living-lighting/festival-lights

I've had my eye on these but haven't pulled the trigger just yet. Will likely by them when it's a bit warmer in the northeast.

Those look similar to "cafe lights", they sell them at Target, and you can often find them used in classified sections of wedding website forums.

I just saw these at Target. There seems to be two similar styles, but the ones by Smith and Hawken are the closest.

They look like medium base commercial string lights - I found some available here/not cheap, but you can keep them up all year.

http://www.budgetlighting.com/store/agora.cgi?product=Light%20Strings%20Commercial&xm=on&TROD=|Light%20Strings%20Commercial#.UOtNy2duXRQ

I've actually purchased from budgetlighting.com - the link keltrue posted above. He/she is correct in that they're not cheap, but they're definitely quality, and I've used them for multiple event set-ups. An amazon search for "bistro lights" will turn up a bunch of options in various price ranges, but I've found that the black corded ones are harder to come by.

Thank you! kitchners always come through.
Carolyn

Carolyn - please note that there are two components to these strings. the electrical cords that the sockets are attached to and a cable to suspend the light string from.

take a look on etsy too, after some scouring you can find some nice and relatively cheap outdoor lights

to find industrial outdoor string lights, like the ones featured in this article., try bulbtronics.com