I am a scrapbooking addict! I'll try to give you some suggestions of things to consider and some websites you might want to visit.
First -- how long do you want your scrapbooks to last? If you are just doing them for fun, and don't plan on keeping them for long -- you can use anything you want in your albums! If you want keep them for a long time and possibly give them to other people, you will want to make sure everything you use in your albums is acid and lignum (sp?) free. If you shop the scrapbooking section in places like Wal-Mart, Target, etc. you should be ok. There are also tons of scrapbooking stores across the country and online.
First consider what size album you want to use:
12 X 12 is a common size. It allows you plenty of room for several pictures per page, or single larger pictures. One drawback is that it doesn't usually sit well on bookshelves.
6 X 6: This is a fun size, but if you are planning on including typical photos (4 X 6), then you are seriously limited in layout options. If you can and want to resize pictures and print at home, this is a nice size -- it is easily portable and fits on bookshelves nicely.
81/2 X 11: This is a great size for bookshelves and common size paper. You can print your own backgrounds if you like, no need for a special printer! However it is harder to do a layout with this size. Symmetrical is usually easier. It is also hard to find patterned paper in this size, so you usually have to cut it from the 12 X 12 size.
There are also tons of mini albums out there - tag books, etc. With these they are great gift albums and very portable. They can be more challenging for a beginner if you use photos (re-sizing/printing yourself), but they are quick and you can feel that sense of accomplishment quickly!
Once you have determined the size you like best, then you can get into which type you like: Post-bound -- screws are used to add or take out pages. They are sturdy, but a pain if you are taking pages out often. Spiral bound -- you have a set number of pages, you can't add more, and if you take any out, you will just have to rip them out and throw them away. There are a few other types out there, but these are the two most common. (I use post-bound 95% of the time)
Supplies you need:
A paper cutter - it needs to be a large size one, cause most paper comes in 12 X 12 size. I recommend the Fiskars one that typically sells for $40.00. It has clear gridlines and the rolling blade has more accuracy than the cheaper paper cutter they sell. No matter which one you get, you will want one pretty quick, cause cutting long straight lines is hard!
You need glue that is made for scrapbooking -- Elmer’s and such will turn your album brown over time because of the acid eating it away. You will need a "wet" glue for thicker item you put in your book, and you will need double-sided tape or "tabs" to put paper and photos on your pages. There are many different kinds and brands. I recommend the cheap box of 250 tabs for beginners. It is usually about $3.
You will want acid free markers. There are tons of them, and you can get them in sets. I bought sets, but I rarely use that many colors. I suggest basic black and then buy what you need as you go.
You will need a ruler (unless you have a paper cutter with clear gridlines that you can use!)
Some folks will try to talk you into decorative scissors and punches, corner punches, etc. I hardly ever use these, so I wasted money on that kind of stuff.
That is the most basic set of things you will need to scrapbook. After that, you can look at pre-made embellishments that you want to add to your pages.
I also recommend that beginners start with a recent topic/recent photos. This way you have fresh memories of what happened! You also aren't tied down to trying to gather every photo of one period of time or one person -- stuff like that.