Filewatcher compiler for watching different files
Sort your imports alphabetically. Make it easier to find.  - Core libs first, then 3rd party.

import multiprocessing
import threading
import os
import time


Constants are typically in all caps.

file_lock = threading.Lock()
update_interval = 0.1


If you have some TODOs, a common practice is to use code tags.

# FIXME:
# TODO:


It's not a must standard, but it is something that is easily recognizable.

class FileMethods(object):
    def a_import(self):
        # do some sort of file manipulation


Ditto on the docstring. Include a desc of your attributes as well.

class FileObject(FileMethods):
    def __init__(self, full_name, compiler):


I would change

self.concat_name = name + '-concat' + exstention

self.concat_name = ''.join([name, '-concat', extension]) # Assuming extension was a typo.


I don't see this method being used anywhere. You also have an if statement further down 
in your code. I would remove this if your not using it. Also, I probably wouldn't create a method for this unless I had to write this out more than 2 times. I only see one instance in your code.

def exists(self):
    return os.path.isfile(self.full_name)


Is this script meant to run interactively? If so, I would suggest adding an interactive flag.

So you can run this in automated fashion (maybe with a config file), or a -i so I can be prompted for input. Also, I would change your print statements to the nicer print statements. They 
also add more flexibility. Consider using argparse for this.

print '%s updated' % self.file_name

print '{} updated'.format(self.file_name)


Docstrings

def sub_mod_check(self):


Ditto on the print statements:

Use .format

        print 'Adding %s with %s as compiler' % (obj.file_name, obj.compiler)
    else:
        print 'File does not exists'


Consider using a main function or method to wrap your logic into when calling your script.

if __name__ == '__main__':
    iw = threading.Thread(target=input_watcher)
   s fw = threading.Thread(target=file_watcher)

if __name__ == '__main__':
    main()