As for the weapons...I've only recently started practicing kobudo but I've done some research about the origins of the weapons.
Bo:
Staff, generally about 6 feet in length. It was used for various purposes, such as a walking stick or for carrying buckets of water across the shoulders. In the bo kata that I have seen nearly all of the moves are with two hands to maintain control of the staff.
Sai:
Made of metal, three prongs with two shorter ones on either side of a longer one. I'm not exactly sure of the previous use for these but I've heard everything from the fact that it has always been a weapon, to the fact that it was made to put holes in the ground for planting. I've just made it about 90% of the way through my first sai kata...tricky little buggers to keep a hold of.
Tonfa:
They are made of wood and look like a night stick. They were used to spin stone wheels to grind grain.
Nunchaku:
Two sections of wood, each usually a bit shorter than the length of the forearm, connected by rope. Again, the origin of this weapon varies from a painful set of handcuffs to the bit and bridle of a horse...I'm inclined to agree with the latter.
Kama:
A pair of, basically, evil looking blade things. Each is made of a handle a bit longer than a foot in length with a curved blade. They were used as a farming sickle (who would have thought of that?
)
Tekko:
My favorite weapon, as they require very little coordination to hold on to. They come in a pair, one for each hand obviously, and are "attached" by a hole that goes over the middle finger. Usually the ends are a bit pointy, which can be used to puncture, split muscle, etc...all sorts of nice things. They were used to make hauling up fish nets easier.
Eaku:
If it looks like and oar, and works like an oar, then it probably is an oar. Eaku were used as oars. They are made of wood and could be used to fling sand at an opponent.
Tanbo:
Two sticks, basically, between 2.5 and 3 feet in length. Again, the origin of this weapon is a slight mystery to me, but I've heard that they could have been drumsticks.
Nuntebo:
Quite possibly the coolest looking weapon, it's basically a bo with a sai stuck on the end with one of the shorter prongs bent backwards. What was it used for? No clue.
Hope that provided some information that you will enjoy absorbing.