I've used AngelList. To be honest, I've had better luck with local connections outside of the industry. My experience with it (which is biased) is that depending on the industry you want to invest in, AngelList only serves those who already have investors or angels. In my humble opinion, to get in on the ground floor your need to attend conferences, talk to young people, see what new thing their friends think are cool. Again this is dependant on the industry your in, for example-- mining companies often won't be found on angel list. Every one who creates an app though... You'll find em there.