ftp problem please help

i recently bought a ready made site off ebay (bad idea) and everything was going fine till my hosting people messed it all up and deleted everything and to top it all i cant get hold of them (technical support dont work and they dont seem to have a website), lucky i have a backup of the entire site on my pc and want to transfer it all back using ftp but here is where it gets a little strange.

I downloaded smartFTP to get my site up and running again but when i try to connect to the location that cpanel tells me in the ftp management screen it just says cannot resolve name, i tried using the url that i use to login to cpanel normaly and my user/pass but it dont work.

Do i need install any software on my webspace to get ftp working??? i looked using file manager and all that is there is 1 folder called trash.

can someone please help me.

thanks

monkeyboy