If I don't have someone to personally recommend to prospect, I tell them to post an RFP at VAnetworking's job board. I explain that it's free to post there as well. I always make sure to use my affiliate link, then I get a $5 referral.
I'm not sure of the best way to find VAs to outsource to. I have VAs contact me on my website all the time about working together and I usually take a look at their website to see if its someone I'd be interested in working with. Then I keep their contact info on file with what they do.
I've posted RFPs myself and have found a few good connections for outsourcing as well.
Maybe we should start a thread in the forum in the VAinsiders area and put our information so we can all learn a bit more about each other. Maybe something like:
Who do you work with:
Or something, and we can create a little database on our VAinsiders Forum.
Maybe Tawnya has some ideas on that.