Buy as dual channel Kit or 2 identical rams?
 

im trying to buy a 1gb memory stick on ebay. I understand for desktop PCs, I need unregistered, non-Ecc, unbuffered, low density ram. but if I want to run dual channel, would I need to buy memories in a specific dual channel kit packet? or can I just buy 2 of the same identical ram that doesn't state itself as a kit?

to run more than 1 slot of RAM, as long as the type is supported by your motherboard and the types are the same, the amount of memory within each dim doesn't matter. Running 2 of the same can improve the performance allowing your OS to treat them the same.