New Motherboard for RAM upgrade.

Hey guys,
I have a Compaq Presapario F700 Notebook with 2x 1GB RAM and an NVIDIA GeForce 7000M / nForce 610M Graphics Card and a Conexant High Definition SmartAudio 221 Sound Card. This is not enough to run what I want to run effectively. I looked into upgrading my RAM modules but my Motherboard can not take any more RAM than already installed. It's the default from-the-box Motherboard for my system. So I wondered, "What if I get a new Motherboard that can hold more RAM?"
So, I wondered if anybody could point me in the direction of a Motherboard that supports 4GB RAM and works with the rest of my system?
Is it worth doing this at all? Would it just be more appropriate to buy a better laptop? (Bearing in mind I'm on a 15yr olds' salary of pocket fluff and chewing gum with only birthday and christmas money to fuel my life)?

All help and comments are greatly appreciated.
Thank you all who offer help.