I am new to selenium IDE

Can you plz guide me how to proceed with this scenario

I have a search box in the application.

i want a javascript prompt to enter the user's search criteria

and that should be taken as input to the "search" field in my appliction

Quite similar to the folowing action in QTP

senter=inputbox("enter search criteria")
browser("browser").page("page").webedit("search"). type senter

well, i did try finding out but am not successful...

Thanks & Regards,