There are a lot of things to learn about lists. A good reference to keep handy is the docs on the Python List Class.
The Python Standard Library
Lists are introduced in the Sequence Types category. A quick search and other documentation for List will surely surface.
The most common way we see of adding to a list is
list.append() but as we've seen above, it is not the only way.
my_list = 
my_list += ['new element']
print my_list # ['new element']
The counterpart to
list.insert(), which inserts a new element at the front of the list. When we give an index as the second argument to this method, it will be inserted before that index (becoming bound to that index).
We can also add to the front of the list with concatenation...
my_list = ["newest element"] + my_list
print my_list # ['newest element', 'new element']
The difference between direct concatenation and appending/inserting is that we can append value only and a new element is created for it using the methods, but must create a list element when concatenating.
Fairly soon you should come upon list slicing, which is a very powerful tool that will allow us to insert anywhere in a list.
my_list = my_list[0:1] + ['inserted element'] + my_list[1:]
print my_list # ['newest element', 'inserted element', 'new element']
Again, we must create a list element of any length in order to do this.