I've been using xe.com to transfer my entire salary from USD to EUR and it's great. I investigated Transferwise but didn't switch because it didn't seem like it was any cheaper.
Just google it. There are several of them (I guess it's not a really high barrier to entry). Hifx, currenciesdirect, torfx... I've not tried any of them.
For larger transfers (ie above £5k/$6k) you have a slew of them; Global Reach Partners, Moneycorp, World First, and Rational FX to name a few.
Disclaimer: I am a co-founder of CurrencyTransfer.com, an aggregator of some of the above larger transfer companies.