Re: Printing Advice
When I do it for my job (I personally do it mind you, saves money, but not time, etc), I use address labels. I simply use Excel and Word to merge the data, and print out the labels. I have a friend who is a printer, so I get an insane price on them, and just do it myself.
If you plan on doing a monthly post card, that is 500+ or around there, consider metered postage. It's a lot simpler then putting the stamp on yourself. Though I'm not sure if postcard postage works in them..., I drop them off at my buddies place, and he takes care of the postage for me.. not sure if he does the stamps or what.
If you don't have the time, or the people, I'd recommend one of the one stop shop places
Just remember, most online sites will require a certain picture format, a certain resolution (i.e. 72 ppi or 300 ppi etc), and also I hope you are using printing colors, not web colors (cmyk vs rgb), because they won't print out the same... there are pantone conversions out there, if you are using the wrong colors.
If you're not remembered, you never existed.