I would like to add print services to my portfolio but don't know what kind of print paper material would work best. I'm fairly close to an office supply store and would like to figure out which program would be best (skilled in flash and photoshop) and the most cost effective way to go about it.

Print would include:

posters
book covers
flyers & brochures
cd/dvd packaging
book covers
business cardsI was thinking of logo design and illustrations are easy but the rest might be costly. I haven't found any guides on this issue through this forum. My first cost effective idea would be use a free service like cafepress and brand products on a product need basis and order them in a private cafepress merchant shop and charge the client the value of the product plus a fee for the design. That way it is private labelled and professional. You see cafepress doesn't charge for setup or on anything not sold, only the base price of the product and shipping costs. Is it worth it though or is there a similar way of doing this?

The Cafepress idea seems like a good one,
but dont they take your image and print it themselves? Cause youd have to make sure they were printing them like you want.
Or can you sell things via cafepress in the sense that you recieve the order and send it out yourself?

Right, via cafepress in the sense that you recieve the order and send it out yourself. They take your image and print themselves, i have ordered products from them before for my own personal projects and the quaility is excellent. The only downside for me would be: the canaian to us dollar exchange rate, price for base price (but would be fine since i would then bill the client), and the delivery charges plus time.