Buy all the basic supplies: pencils, pens, erasers, rulers, a calculator, spiral notebooks or loose-leaf binders, computer disks and a backpack. Splurge on a packet of no. 2 pencils, which you'll need for those pesky scantron tests.
Select ink pens that are easy to write with (ballpoint pens can be messy) and keep at least two writing implements in your backpack. You don't want to be empty-handed if one should break or run out of ink.
Look for notebooks that include folder pockets for storing handouts or buy binders to hold handouts and spare paper for notes.
Select a calculator that doesn't have too many functions. Chances are you won't need to use graphs or charts unless you are a science, math or engineering major. You want to be able to recognize the function buttons quickly.
Most schools work with IBM computers. If you plan on using a computer in the school's library on on school's grounds, bring disks with you to save your work. Check with your school's computer labs if in doubt.
Purchase a day planner or organizer to keep track of assignments and tests.
Invest in a good dictionary that gives multiple definitions of words as well as their origins.