Let me know what all the form load involves.
For example, if you are reading some data from tables/files, doing some initial process.
I don't know what kind of form you are mentioning. In general, divide the complete process of form load into number of tasks, you may write different functions/procedures. Call these procedures/functions from a main program, where in parallelly keep displaying the progress bar with some progress.
By the way what's ur front end development tool?