Only just saw this thread and while I am late to the show this info might be on some use.
If you have never been fishing before then theres a couple of things worth a mention before you even start.
1) Check the weather. If its going to be blazing sunshine don't forget sun cream. You will burn to a crisp by the waters edge.
2) At least be able to swim to some degree in case you fall in!
3) You will need a rod license. I think it used to be that anyone under the age of 14 could fish without one but I've not been that old for a very long time now! You can walk into your local post office and get 1 or 8 day licenses or a yearly one. If you are just going for the day it might pay to start with a one day license.
http://www.postoffice.co.uk/rod-fishing-licence
4) The pool or canal you choose to fish may require additional payment for a days fishing. This is typically anywhere from £1.50 to (the extreme) £10.00. I would advise finding a local commercial fishery for a couple of reasons. They are often stocked extremely well with all manner of coarse fish, big and small. The facility's are often very good with toilets on site and more often than not a café or shop you can buy snacks and drinks.
If you are completely new to fishing and have no tackle what so ever I would suggest getting what is called a whip. This is a telescopic carbon pole that ranges in length from 1 meter upto 10 meters. For somebody new to the sport a 3 meter whip is more than adequate. When using a whip there is no need for a reel as the line attaches to the tip of the whip with a connector. A rod and a reel can be quite confusing for a beginner as you have to learn to cast and also theres always the chance that the line on the reel will tangle, you could end up spending the day trying to unpick knots!

With a whip however you simply swing the terminal tackle out in a underarm action and you are fishing. A whip is not really designed for big fish but instead its designed for catching lots of small fish. I think this is important when somebody goes fishing for the first time (catching lots of small fish) because you get used to handling the fish, unhooking the fish and also you wont get bored as the float is going under (hopefully) very often
Get yourself to a local tackle shop and have a chat with the people in there. More often than not they will be very helpful. Just explain you are testing the water and don't want to spend hundreds of pounds on gear and they should (if they are worth there weight) help you out. Its in their best interests to do so as its potentially another person(s) coming into the sport and another future regular customer.
Below is a simple guide to whip fishing.
http://www.youtube.com/watch?v=8epGyuBSP9c