Purchasing Arduino & Accessories in the UK (Great Britain)

MarkG:
After looking at some suggested site, I have to say that I am now leaning towards a Pi.

Precisely what I would suggest.

MarkG:
The reason being is the fact it has more to offer than an Arduino, that does not mean that I am not going to get one!

There are other options, but in general, the Pi is the cheapest to get the job done. If you are serious, I think you will.

MarkG:
But the cost of a Pi, found a starter kit for £40 which includes the case, 8GB SD and its the Model B with 512MB onboard Ram.

The case can be quite (inappropriately) expensive - some are priced similar to the Pi itself - but you really do need one.

MarkG:
I know that the Arduino is not meant to be a PC but

And that is precisely the case.

MarkG:
it would at the moment be something that I can easily set up,

I don't think so. Setting up an Arduino as a Web server is anything but trivial. For the Pi, there are many tutorials, if not purpose-built packages.

MarkG:
when you break the cost of getting an Arduino + Ethernet and power needs for the unit, we are talking easily three times the price of a Pi.

Actually, finding a power supply for a Pi (or Funduino) is not so easy either.

In short, the Pi will do the job as web-server, though admittedly I have not done it yet myself (and it was the reason I got the Pi :D).

MarkG:
All I can say at this moment is I am disappointed that I can't afford an Arduino at this moment in time or for the foreseeable future.

Oh, I very much doubt that! A plain "Pro Mini" or really cheap clone plus a USB-TTL converter and a breadboard is a fantastic way to start with them and dirt cheap, rather than wanting to make it into a full-fledged PC, web-server or whatever.

Interestingly, a Pi can itself run the IDE to program the Arduino.