Which is the best CP for making the Virtual servers. Like serverXchange is good but its very expensive.

I assume you mean a VDS, or whatever term is popular now. FreeVSD is free but it will give you enormous headaches, take for ever to install. You will need a found understanding of linux. If you want to make it usable, you will need to be able to write some scripts, and hack some current scripts. Be prepared for a long journy in my opinion. There are some concepts that are not really made clear, which will come back and bite you later. Good luck. Btw, its not a control panel that allows for vds, the software is the backbone of it.