older used white Macbook
How old? The RAM specs among the different models are not same. Macbook2,1 for example uses DDR2-667 PC2-5300 200 pin SODIMM.
The good news is you can find RAM for any Macbook no matter how old. There are many vendors out there. I use this one: http://www.macramdirect.com/macbook.html#mb3
As for SSD you have to make sure the physical fit is correct. This is a good overview.
http://macs.about.com/od/macupgrades/qt/upgrade-your-hard-drive.htm
You have chosen wisely for your "first computer surgery". Both these are relatively easy to do. For the hard drive replacement you will need a Torx #8 screw driver.
There are numerous guides, including videos, on line to help you.
Good luck.