Sorry mate you took it completely in the wrong way. I would get it sorted asap otherwise the caliper could warp. I think thats whats happened to mine.
Right, you could either go down the route of buying a caliper repair kit and refurbing it yourself, http://www.biggred.co.uk/ There is also a good tutorial of how to do it on this site.
Also if you need it, a previous post on here, http://www.lexusownersclub.co.uk/forum/index.php?showtopic=66490
You could buy an already refurbed caliper and trade your old one back in.
Or obviously just buy a new one, but to be honest, I wouldnt bother IMO because chances are it will just do they same thing.
Hope this helps