I would like to change a florescent ceiling light fixture in my bathroom to 2 wall fixtures. How do I split the electrical supply from one to two?

Going to have to install a nail on new constrution box in the attic to make the connection, (it gets nailed to the side of the ceiling joist) and a blank cover for it. Install a new 14-2 with ground wire from inside that juntion box to the old wiring with yellow wire nuts and just twist the bare grounds together with a pair of plyers nice and tight, and run it down to the first light fixtures juntion box that your going to have to have inside the wall, run one more wire from that box over to the last box where the lights going to be mounted.
For some pretty pictures you can Google " wiring light fixtures"

Sandy:

Think twice or even three times before you go ahead with that. A ceiling mounted light fixture shines light on the ceiling at a sharp angle, making every glitch in the drywall or plaster stand out. If you move your light fixture to your walls, then every little glitch on your light fixture walls is suddenly going to make itself known, and then you'll discover the need to repair any drywall or plaster problems too.

To see what potential problems might come up, have a friend hold a bright light at the proposed wall fixture locations, but only an inch or so away from the wall. Now, you check the wall for problem areas.

By looking up an electrician in thee local phone book. Sounds like you may be over your head on this one...

Second vote on calling in a pro. not to insult but this is a very basic electrical change - yet still needs to be done in the proper way. Asking on this board shows that you have very little electrical knowledge. Doing this wrong can be dangerous to both you and your house.

Have a pro do this or find a friend with electrical knowledge show you how to do this.