I'm a size 8 too and my Toms are a W10...presume American sizes.
I thought I couldn't wear Toms as I tried a pair of 8s once that were far too tight. Then I tried a pair that had been on the sale rack for ages and they felt fine - I think they'd been stretched out by millions of people trying them on.
Anyway, I've worn mine a few times now and they are the most comfortable shoes ever (apart from Birks). They are still snug but they have stretched out a bit.
When i tried a pair on instore i found them way to tight so didn't buy any, but then like the sucker i am found some online in the Office sale and so i bought a lovely pair in dark grey with a lush fleece lining. When i tried them on i thought on no too tight again, but with minimal wear they are fine now. Although you are meant to wear them without socks which helps!!