Quick Answer: It depends on what you want to spend and whether you just want a good calculator for this one course or if you want a good calculator for future uses.
Here are my brief recommendations:

Line 
Brand 
Model  Price 
Store 
Fractions 
Graphing 
Function Eval 
Notes 
1 
TI 
TI36X Pro  $18.87 
Walmart 
Yes 
No 
Yes 
Best nongraphing calculator for this course 
2 
TI 
TI30XS Multiview  $13.87 
Walmart 
Yes 
No 
Yes 
Excellent nongraphing calculator for this course 
3 
Casio 
FX260SLR  $6.97 
Walmart 
Yes 
No 
No 
Good nongraphing calculator for this course 
4 
Casio 
FX115MSPlus  $15.54 
Walmart 
Yes 
No 
No 
Good nongraphing calculator for this course 
5 
Casio 
FX115ESPlus  $16.45 
Walmart 
Yes 
No 
No 
Good nongraphing calculator for this course 
6 
Casio 
FX300ESPlus  $12.99 
Walmart 
Yes 
No 
Yes 
Good calc. Easier to read than the FX115MSPlus 
7 
TI 
TI30XA  $8.44 
Walmart 
Yes 
No 
No 
Good nongraphing calculator for this course 
8 
TI 
TI30XS  $13.87 
Walmart 
Yes 
No 
Yes 
Excellent nongraphing calculator for this course 
9 
TI 
TI73 Explorer  $71.00 
Walmart 
Yes 
Yes 
Yes 
Good graphing calculator for this course 
10 
Casio 
FX9750GII  $49.88 
Walmart 
Yes 
Yes 
Yes 
Very good graphing calculator for this course 
11 
TI 
TI84Plus SE  $99.00 
Walmart 
Yes 
Yes 
Yes 
Excellent graphing calculator for this course 
12 
TI 
TINspire CX Graphing  $139.00 
Walmart 
Yes 
Yes 
Yes 
Superb graphing calculator for this course, but also overkill for this course! 
13 
HP 
HP50g  $105.00 
Walmart 
Yes 
Yes 
Yes 
Superb graphing calculator for this course, but also overkill for this course! 
14 
TI 
TI83  I don't recommend buying this calculator now (buy the TI84 instead), but if you have one from high school, it will be a great calculator for this course. 
Note: These are probably not necessary for this class or any other, but the symbolic manipulation capabilities are occasionally useful. They would serve you well clear through grad school. Many students greatly prefer the user interface of the TI. It seems more intuitive and natural. I have been a big fan of HP calculators for a long time and it is my personal preference. Either one will do a great job. If you are seriously considering spending this much money on a calculator, you might want to spend some time researching them and, most importantly, using one to try out the user interface. These are very powerful calculators, but they can take a good bit of time and effort to learn to use them effectively. TI89 Titanium  About 1$35 at Walmart. HP50g  About $105 at Walmart. TINspire CX  About $150 at Walmart. Do NOT get the plain Nspire calculator! Make sure it says "CX" at the end. The Nspire CX has many more useful features than the plain old Nspire for very little extra cost. This is a great calculator, but if all you need is a calculator for College Algebra, it is a lot of overkill.
Created on ... Aug 28, 2007
Last updated on ... Aug 30, 2010