I am about to buy some RAM for my MacBookPro 8,2 and i was wondering if you need to re-install your osx ? I dont think that i got a install dvd when i received it. And then i was wondering what you should do if you want to upgrade the SSD?
If you get a new SSD, you could just clone the old HDD to the new properly formatted SSD and then exchange the HDD for SSD. Below guides might help you there.
Assuming you're talking about the non-retina MBP, you can easily replace your drive with any HDD/SSD that you choose. You can use Carbon Copy Cloner to clone your existing drive to the new one (in an external enclosure), then swap the drives.