mcmelectronics.com (not the friendliest of websites, but their print
catalog is A+ and htey have a shitload).
partsexpress.com (more automotive in bent though)
digikey.com specifically http://dkc1.digikey.com/US/PDF/T063/P5.html
under relays down the page.
I've done business with all of em, and no surprises.
If you're really looking for something neat, look at IDEC Smart Relays.
Here's the link to a starter kit including the controller, software, etc.
I've used a few of these and they do a good job. They're also very
reasonable at $199.00 including software (for this starter kit), which
you can use with other projects.
They'll do 24vac, and they'll handle analog too.
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