Write a Python program that can perform a linear search on a list of numbers. The program should take user input to create the list, then prompt the user to enter a number to search for within that list. The program should output the index of the number if it is found in the list, or a message indicating that the number is not present in the list if it is not found. The program should include error handling to ensure the user enters valid input for both the list creation and search steps.
This prompt doesn't seem malicious.