The 3 commercial printers I usually use to print my announcements are all located right here in SoCal. They are: "Overnight Prints" (not really, but they can be pretty fast); "Americas Printer" (located in Buena Park); & "Modern Postcard". Usually, the larger the volume needed, the more inexpensive the job. Once you've done business with them, "Overnight Prints" sends you emails regarding special offers that are especially low-priced.
I'll put the web-site links over to the right on the blog. With all 3 companies, you design the card & upload it for printing. As Tyler would say: "Easy-Peasy."