The NEX-5 has no inbuildt options for timelapse recording. And there is no remote controls with timer available for the NEXX.
The solution is to modify some remotes to work with the NEX. First by a supersimple ir remote RC-C3. Then buy a wired timer remote for a sony alpha or similar. Cut the wire from the timer remote and solder to of the leads to the shutterbutton of the simple ir remote. Some wlcro on the ir remote and the NEX: Ready to shot some timelapse !
Here is an example of some timelapse shot with the NEX-5: