Mask and replace object on a moving item

Question

I am new to CS4, and not too familiar with Photoshop or After Effects, and I was wondering how would be best to do this:
1 - I need to mask the label on the cover of the Blush jar, where it says "MICA BELLA cosmetices" and replace it with another name. The photo moves from left to right in the video so whatever change I make has to move with it. In fact there are a few photos in which I need to do the same, and the jars are at different locations and angles.
2 - Also, at the botton of the pic, below the white line I need to put another word to cover "MICA BELLA" and I'm wondering how best to copy the color scheme across the lettering.
I do not know how the original was created.

Answer 1

Stabilization is the process of stabilizing footage, tracking is the process of synchronizing/adding elements to moving footage.
Sorry if the answers so far are not what you wanted to hear, but the reality is that, althought it might SEEM like a simple task, tracking replacement content into moving footage can be quite complex.  There are huge teams of specialists dedicated to this very task on many TV commercials and films these days.  It's crazy to think you can attain that level of skill with a tutorial and a couple of hours.
In my opinion, so long as there's not too much dimensional distortion in the camera move, the easiest way to achieve a basic result would be this:
Export a frame to Photoshop and clone out the text on the lid.  Then select the whole face of the lid and place it on a new layer.
Save the layered PSD and import to your AE project.  Place the "clean lid" layer into your comp and align it perfectly over the old lid.
Now it's your choice - learn how to motion track, or simply move through frame by frame and adjust the position of the clean lid at every frame.  If you set a start position and an end position, hopefully the lid will be in almost the right position throughout the move, and you'll only need to make small corrections.
When you're happy with the result, add your text layer, use Corner Pin to alter the perspective, and attach it to the Clean Lid layer using parenting.  You might want to use a Transfer Mode like Screen to make it blend more realistically with the light falling on the lid.  (You might prefer to skip that step and just add the text to the lid in Photoshop, if there's no prespective change during the camera move.)
Use masking to remove the coloured text in lower frame.  Use Layer Styles to create a matching gradient on your replacement text/log