Doing your own music at a wedding

As the title suggests, has anyone actually tried doing this?



Any tips on....



- Getting hold of the music (it's gotta be via an ipod / iphone so I am guessing Itunes is the only way)



- Playlists (I know I need a mix of cheesey rock, cheesey pop, love / slow dance songs and decent disco music.



- Is there a program I can use to make the songs merge from one to the other with the 4 - 5 second silence?



Any other tips would be greatly appreciated!!