Well, it's four times 2GB!
To be honest, unless you want to be able to carry around literally hundreds and hundreds of photos in the camera (maybe even
thousands, with a combined storage capacity of 10GB) without downloading them to the PC, then you probably don't need to go for the maximum possible capacity (see CF prices [broken link removed]). I have a single 1GB card and it's usually more than adequate, because I sit at a computer every day and I have a portable card reader/storage drive to back up to when travelling. Also, there's a school of thought which says it's better to have 4x 2GB cards than 1x 8GB. If a card fails (which is always possible), you've 'only' lost 2GB worth of data instead of 8GB...
That said, given that 7dayshop have a flat shipping rate (£3.95), it makes sense to buy several items at the one time. Maybe get a 2x 2GB or a single 4GB CF card and have a look at their special/clearance items for any other bits and bobs you might need?
7dayshop don't do them (more's the pity), but the first thing I would recommend would be to put a protective skylight/UV filter on the front of that nice lens! You can buy them over the counter, or pick them up more cheaply on [broken link removed].