Well I think you are talking about AM2 vs 939. Those are just different socket types for the processors. The only real difference is that AM2 can use DDR2 memory while socket 939 uses DDR1 memory.
Uh, AM2 is a new socket for processors designed by AMD. The two major chip makers are Intel and AMD. Just search on newegg.com, and you should get some hits.
Motorolla is pretty big. Until MAC went to Intel processors, they used Motorolla processors. Also, VIA is another manufacturer and is known for their ability to run without a heatsink... Lhuser!