Where do you buy good oil?

I don't want to start another "which oil?" thread, I'm just wondering where those of you in the UK buy decent oil? I can't seem to find any anywhere.

I'd like to get some high-quality synthetic.

Thanks!

I'm not in the UK but I just use Yamalube. Every Yamaha dealer sells it.

We don't seem to have the choice over here that you get in the US. But surely, any decent bike shop should have a range of oil.

I bought Silkolene fully synthetic from my local Yamaha dealer as there was not much difference in price compared to buying it online, plus I like to support my local bike shop. Have a look at this site Motorcycle Engine Oils their prices don't seem to bad for fully synthetic oil.