disc brake problem!

edited February 2011 in MTB beginners
Hello All

Just doing my first build and have a problem......

Have taken the pads out of my front brake, a Tektro Auriga Comp. The problem is that The caliper has come out and the whole thing is oily now, I can't seem to get the caliper to go back in enough to get the pads and clip in...

What do I do?

Really a shame as the bike was just about ready to go, now I am grounded until I get this fixed!

Thanks to anyone who can help!