The standard print portfolio size for modeling is 9″x12″. When setting up shoots with photographers remember to request 9″x12″ high-resolution RGB .jpg files on CD for your book! If you don’t ask specifically for that size and resolution you will not likely get images you can use for your print portfolio.
9″x12″ prints are available online from Adoramapix. [link] The price is $2.79 per print and shipping is $5 regardless of how many you buy. It’s easiest and cheapest to place a big order all at once since you can just upload everything in one sitting and pay for shipping once. Prints should arrive to your door in around seven days so order prints well in advance of your interviews. Another option is having your prints made at your local Costco. They can make 9×12″ prints and I believe it is same day service.
The industry-standard portfolio is the Scuba available for around $60 (phone them for shipping prices) from [link]. Ten pages should be enough, as each page is double-sided and can hold two prints. Itoya makes a budget portfolio for around $45 that looks to be nearly as good as the Scuba [link] If you’re even considering visiting agencies in a major city, get the Scuba. One of the best articles written on the subject of creating your book is by Dan Hood on the ModelMayhem forums (sixth post down). [link] Dan gives excellent insight as to which shots to keep in your book and which shots to avoid.
Newmodels.com is also a great resource for information on the industry. [link] The author of that website is a respected industry insider named Roger Talley who penned an informative book on the subject titled The Professional’s Guide to Modeling.