Some really cute ideas for gifts (especially for pre-teens and teens) are the chipboard albums, some of which can be found here and Cosmos Cricket's blackboard albums, here. Kathryn Estry has blank templates the size of Cosmos Cricket albums for sale at Gotta Pixel, here. This includes 5 templates, but they can be purchased separately as well. Searching I found people using tags, cds and various other media for completing "brag books'.
Pages can any size you desire and can print (or have printed). Popular sizes include 4x6, 5x7, 6x6, 8x8, 8.5x11 and 12x12. It will also depend on whether you want a bound volume or a binder that you can add to.
Binder albums are perfect for hybrid pages where you print out the page then add the elements to them. Bound volumes are perfect coffee table books (and are easier to store on bookshelves).
There more than a few companies that you can find to print and bind your scrapbook pages. Shutterfly and Inkubook come to mind, as I just got emails from both.
If you decide to have your pages bound, I highly suggest that you take a moment to read what Simply Yin has to say about preparing your page, here, here and here. She also has a link to a more comprehensive article by Wendyzine at The Daily Digi.
Again, this is suppose to be fun and provide your family and friends with documentation of your or their life or an important event.
Below are a cover page and pages 1-3 using Kathryn's template for the Cricket "Abby" album of a family trip to Hong Kong.
Cosmos Cricket Abby template (c)Kathryn Estry; Font: Pea Valerie