4getmenot, if I supply you with the live rat, please can I watch you pick it up by the tail?? lol You may get away with it with a mouse, a rat will take chunks out of you, it is a sport of pastimes, being able to hold a rat up by its tail, I don't recommend trying!!
gloop, by all means put a couple of rat traps down, but you may also be advised to put down a load of rat poison as well, you are probably assuming that it is only one rat, that may not be the case, hence the poison.
Rats carry many diseases, so keep all your work surfaces extremely clean at all time, rats do not stop for a wee, it just trickles out of them as they travel around. Weils disease is potentially very dangerous and carried by 50% rats and passed on through their urine, so take the cleanliness thing seriously. If you have a dog, make sure it is up to date with its jabs, one of them is Leptospiroses, the dog form of Weils disease. They don't call me RATTER for nothing!!
Good luck!!