Anybody know if its possible to have an Tremolo Bar (floyd rose perhaps...) fitted to an Epiphone Les Paul??

Also if anyone knows how much $ this would cost its greatly appreciated.
You would be better off buying a Bigsby or a Les Trem, they would be a heck of a lot cheaper than having your guitar routed for a floyd. Plus the Bigsby looks awesome.

What bridge is on their now? If its a TOM well then you have a neck angle. Which means the only way you can chuck a floyd on is if it is a bolt on neck. You need to take the neck off, shim it so theres no neck angle. Take the old TOM out and dowel the holes. Measure your scale length (nut to 12th fret x2) Put the floyd so that the part of the saddles where the string first meets it is exacly your scale length away from the nut. Then mark out where the studs should go and then you've got to start routing. Note: you will have to route out A LOT of the guitar body, including where the floyd would go and underneath where the claw and the strings would go. Its a lot of work...

All instructions on how to do it can be found at the Ultimate Floyd Rose thread. Search it

Good Luck