Dell have a guide on their homepage how to install a new memory : ) I will post the link if I find it.. its 200pins DDR2-533Mhz SODIMM you are looking for. The maximum amount of memory is 1GB module / slot.. so maximum 2GB for hole system.. gl!
Yup, just go to their site, click on support, enter the info for your system, and go to the html guides. The guide is fantastic with pictures and everything. It's a simple procedure really, take off the back cover, insert the module, put the cover back on, but the guide explains it in detail. Have fun