First off, iFixit usually has fairly simple, instructions on how to do this stuff, but I will warn you ahead of time. Apple typically doesn't sell replacement drives to the average public, RAM they sell as long as it's meant to be user replaceable. I'm not sure how easy it is to do it on the MBP model they currently have on the market. If you have to crack open the case, I would highly suggest bringing it in unless you really understand what you are doing, have the right tools and its not under warranty. If it under a year old I wouldn't do it myself.
Here's a link to iFixit.
http://www.ifixit.com/Device/MacBook_Pro
Since it's probably still under warranty or with AppleCare, I would suggest only putting APPLE memory, I have the best luck with Apple memory PERIOD.
Hard drives? If the computer was out of warranty, I would probably only recommend either an Apple brand hard drive or OWC. OWC is pretty reliable.
But it's pretty easy with this model. Unscrew the bottom screws and there is a connector you have to disconnect. It's pretty easy from the photos.
Please make sure you have a grounding strap, if you don't, GET ONE!!!! BIggest mistake people make is not being grounded, as you can mess the thing up if you aren't grounded.