I always have people ask me about using online printers. Well, here's what I know: There are tons of online printers out there. I've checked in with several of them regarding prices etc. 4Over is a big one, as is Vistaprint. I've seen some samples of their work. My personal favorite and the one I use most frequently is OvernightPrints.com. I've used them for countless projects ranging from letterhead and business cards to postcards and brochures.
I can also speak for their customer service. During the time that I've been using them, I suffered a hard drive failure (more details about that in another post). While trying desperately to recover my files, I made a call to Overnight and they sent me copies of every file I had ever sent them. No questions asked, no fees. They were friendly and very helpful and understanding.
The company will definitely keep my business in the future!