A ceilidh is more of a Scottish/Irish thing than traditionally "British" but they are great fun and perfect for encouraging people to join in.
If you're having a wedding outside the UK you will definitely need a caller. Can you find someone to do this? Where will you get appropriate music? can you get a band that can play for you or are you going to buy a CD/ipod to play?
don't try anything too ambitious so maybe just plan 2 or 3 dances to get people going then revert to normal disco music in between. a whole night of ceilidh is exhausting!
Most ceilidhs start with the gay gordons as this is a nice simple introduction for everyone.
It really helps to have one couple that can demonstrate the dance for all the other guests too.