From an email I just received:
Planned Parenthood Pennsylvania Advocates and PAC have brand new technology this year for our Voter's Guide! Just go to our website by clicking HERE (or go to http://www.pppavotes.org), enter your address, and your Personalized Voter's Guide will appear! You can even print your copy to take with you to the polls!
In a nutshell, Planned Parenthood of Western Pennsylvania sends out questionnaires to all the candidates, then posts their answers (and, sometimes, makes endorsements) on their voters guide. I've always found it to be a fantastic resource, especially with regard to candidates in smaller, local races (like judges, for example) that maybe haven't had as much press as those running for higher offices.