Try dabs ( click here ). They tend to provide technical data for their motherboards, including RAM types, supported processors and so on. It will take a while to get through, however, as there are many motherboards out there.
As for the memory, you'll need to know the type, such as SDRAM, DDR, DDR2, etc. That will play a part in finding a motherboard. Also check to make sure it can support 2Gb of memory (again, dabs tells you this).
Once you found some candidates, use Froogle ( click here ), PriceRunner ( click here ) or similar to find some deals on the chosen board.