What's the error you get with iTunes? And what method did you use to jb?
Generally speaking (very generally) there are two causes of a restore failing: either you set the hosts file to somewhere other than Apple (people often do this without realizing it, which is why I asked about Tiny Umbrella), or you have a baseband that doesn't correspond to the firmware you're asking iTunes to restore (either it's lower because it was preserved during the jb, or higher because the iPad baseband was chosen during the jb).
Essentially, we just need more info than "it won't go through." What actually happens?