www.xl.com
www.lastminute.com
Used both, highly commended, XL the one I have used most for Spain.
Also, believe it or not, Teletext online - much quicker than wasting your life watching pages turn on TV !!!! And surprisingly good for the odd cheapie, even from the big boys who won't use the other resources: last time I flew it was with BA for £30 off of teletext ! A ticket that they would have rather kept empty than make available to the likes of XL or lastminute.....
Good luck
Big envy.
Can I have your Barbel swim while you're away ?