Download the free Skype software and all you need then is any old computer mic and your speakers..
Most folk use something a bit posher ( I paid ?3.50 for a handset type thing that plugs in to the mic socket and goes 'in line' with the speakers so you can switch between the speakers and the hand set ( sounds complex but aint
)
The software is easy to use and easy to set up.. A couple of folk have had minor probs with it but most have sorted it out in about 2 minutes ...
It is certainly bloody handy as more and more firms are using it as well as private folk.. And remember Skype user to Skype user is free..
Skype to non skype user costs but is is SOOOO cheap !
For instance, I have foned Florida John a few times and it is just pennies from the UK !