WILL pci-E CARD FIT IN agp SLOT?

No.
Even if you can hammer it into the slot, the connections are different and you'll fry the entire system the instant it's powered on.

^Best answer, ever^

Just because something looks like it fits doesn't mean you can shove it in there, -giggles-
On a serious side note, PCI-e will NOT fit in a slot it's not made to go in even if it "fits" because like Coozie said they are different connections, you will fry something and wish that you hadn't shoved it in.

He who asks this question should leave the computer case closed.