New to Asterisk?

Ok I have a friend in Peru who wants to make lots of calls to the usa, Currently the idea is to set them up with vonage, is their any benefits to adding asterisk to the equation and if so what are the benefits?

Really depends on the user’s requirements. Asterisk provides a PBX with voicemail, multiple lines, Least Cost Routing, etc. If it is only to make many outbound calls via a single provider, then it probably would be overkill.

Also, why Vonage? If it is for cheap outbound to the US there are two ‘free’ alternatives:

voipstunt.com
voipbuster.com

I use both and they work fine. It is possible to use their provided softphone or obtain a SIP ATA just like with Vonage.