Hi Ge64, there is such a software - it's called ZoneAlarm.
From memory there was 2 versions, ZoneAlarm and ZoneAlarm Pro (this one wasn't free).
You can specify which program is allowed to access the net and lan individually.
You can download the free version here
ZoneAlarm - Free Software Downloads and Software Reviews - Download.com
The only reason i stopped using it was because i got a hardware firewall and stopped using P2P software
Marked as Answered - if this is not what you're after, PM me and I'll look for alternatives for you.