Decide in advance how many copies you'd need, that's the one thing that the printers need to know to be able to do a quote for you. They want to know how large the original is (find out their card stock sizes/dimensions in case they have large sheets - you'll be able to get an entire deck on one sheet that way) and if you'll have camera ready art. Also, if it's in color or just black & white.
They'll probably tell you they'll use a xerox instead of the traditional set up of printing process for color. Color laser prints can be very nice, but they probably won't have the machines that can do that on any sort of card stock, you'd be limited to flimsy typeing type paper.
If you get into color separation, you'll be looking at probably $35 cost to produce each deck....depends on where you go but the quotes are all pretty similar in my area so may be similar in yours too. I went to 9 different places and they all were pretty close in price. They'll look at how many originals you've got (6 cards to a page? How many pages?) and multiply that out. Also if you'll have a back image to put on the cards. Their problem will be in lining up the back image perfectly to the front of the card....their machines are off slightly as the paper is pulled in by the rollers so see if you can do a back image without a border on it.
If you're going to do the cutting on the cards yourself, that'll be cheaper. If they do the cutting, they charge by the 'cut'. They also charge per cut for corner rounding (I got a quote of $54 for 30 decks). You can laminate them yourselves (shop around for low cost sticky lamination paper so you don't need to use a machine for it). But ask if they can do a 'varnish' on the cards, which can be a protective surface too. I couldn't find any in my area who did this though, they said they'd send that to their main office halfway across the state but that it would have to be a minimum order of 1,000 decks. All of them recommended 2ml sticky laminate & that I cut the cards out separately myself. You'd probably have to use a scissors to do that, I don't think a paper cutter could do a clean cut on plastic. At least not for a large project like this.
One place I went to tried to get me to do all sorts of extras--pushing certain papers, etc. You need to look at the # weight of the paper, but FEEL each sample. Some of the higher poundage weights are actually flimsier than the lower # weights, it depends on what the content is in the paper rather than the weight of the paper. Look for stiffness over # weight. And there's more stiffness in the length of the paper than the width, so if your card setup is vertical, it'll 'feel' different in the finished cards than a horizontal setup would be.
For straight photocopy of a black & white deck I found excellent prices at PIP Printing and Econoprint (under $3 a deck for 13 originals and a back image on each). They were better than Kinkos and Office Depot. Same paper, same machines. Same quality.
If you're doing color--check with true printing shops rather than xerox places, as the color separation needs to be done on masters & they'll have better equipment, even if they do recommend xerox there too. Ask to see what ONE image (bring a sample) would look like on any particular paper. The image itself may look fuzzier than you think with color. You have an option of using pure white paper card stock, or one with a tint to it or little textures on the surface. With black & white art, you can get an 'aged' look by using a marblized paper or one of the tan/cream/ivory/papyrus colored papers. For color art though, use white.
