Finding info on Macbook

I am trying to buy some memory for my macbook. I searched and was overwhelmed with the results I found on newegg, best buy, and crucial.com. I was also overwhelmed by the number of responses here.

Here is what I know about my MacBook:

Intel Core Duo
2.0 GHz MHz DDR2 SDRAM
Number of Cores: 2
Cache: 2 MB
Memory: 1 GB
Black
I bought a refurbished model

Do I need any other information about my macbook to make an educated purchase? I'd like to purchse through newegg because of the price but it seems that I need a model number (I don't know where to find that...).

Also, I would like to do this only once, can I go to 4GB or will my macbook fry?

Any help would be appreciated!

You can be sure by using the Crucial Mac system scanner:
Memory upgrades from Crucial.com - About Crucial:Media Toolbox

So today I received my new memory from crucial.com. I upgraded to 2 GB of memory and I couldn't be happier with the immediate outcome.

I feel like it's lightning speed.

Thanks for your help!

(And for the record, I will use crucial.com again. Great service. Thanks for the rec!)