Your cpu is so old now that you wont find any "new" motherboards that will support your current cpu which means you have to buy used or "refurbished" motherboards for you cpu. The easiest solution without getting to envolved in other things would be to replace your motherboard with the exact same. To avoid having to reinstall your OS which would mean backing up your data etc. and hoping you have a OS disk and not just a OS image on your hard drive like most OEM vendors do which my emachines was.
Basically here are your options
1 buy the exact same motherboard and carry on as if nothing happened
2 replace with a newer motherboard which would mean a new cpu, memory, OS purchase, backup data from old hard drive install new hardware install new OS and transfer old data. More than it sounds like you are wanting/know how to do.
3 For the price of all that and if you dont know how to go about doing all that then a $300 prebuilt system would work best for you but a transfer of data would still be needed from your old hard drive if you want anything off it.
More Advanced Micro Devices than Intel