Canon lenses

I have been looking at lenses long and hard the last few nights. I am keen to replace the kit lens on my 400D with something a little more capable. I also want to replace my Tamron 70-300 with something that remains sharp through to the 300 end and with stabilisation. It seems that these two lenses off what I am after.

Canon EF-S 17-55mm f/2.8 IS USM
Canon EF 70-300mm f/4-5.6 IS USM

However - UK prices are around £1,100 for the two. Luckily all is not lost - going to the USA soon where the price is much nearer £800. Now, that leaves some money for a flash doesn't it......

I can see that this photography hobby may be a little on the expensive side! Although a LOT chepaer than my last one (helicopters).