Note: If you're on a tight budget, consider a corded (plug-in) drill. You can get a high quality corded drill for less money. It will be lighter and have more torque (power). And, <drumroll> the battery will never need charging just when you need it most. Unless it's one of the new Lithiums, if you don't use a drill regularly the battery is likely to need charging when you go to use it. Cordless drills are convenient but, they're more expensive and heavier with less power than corded drills.
Another problem with cordless drills is the batteries usually only last 2-4 years even if you don't use them . Rechargeable batteries go bad just sitting on your shelf. Replacement batteries are amazingly expensive. I see cordless drills including a charger and two batteries on sale for only slightly more than the cost of two batteries. So, you may want to think of a cordless drill as disposable, and expect to replace it every 3-4 years. [NOTE: The new Lithium and NiMh have relieved this problem quite a bit.]
Normally you should expect to pay $60-$100 for a good corded drill. A few years ago Makita's model 6408K at $70 was rated high, and (surprisingly) Sears' model 10105 at $40 got a good rating.
That nationally famous consumer products rating magazine rated cordless drills in December 2012.
If you want a drill that can handle moderately large jobs as well as routine ones, your best combination of weight and performance is probably the the top rated 18 volt Hitachi Lithium DS18SAL at 3.4 pounds
If you have big projects in mind and want top power with greater run time per charge, and are willing to pay the weight penalty for it you may want the Makita BHP454 or the Milwaukee 2603-22 both 18 volts, $280 and 5 pounds.
The worst drills were Skill & Craftsman.
A drill gets heavy after holding it for a while. My test is to hold the drill as though you're using it just above eye level and see how long you can hold it there. (Be sure it's with the battery -- display models often aren't.) 5+ pounds may not seem like much until you try this. The whole point of cordless drills is convenience. Adding 2 pounds to a 3.5 pound drill is a lot. If it becomes so heavy it's awkward or tiring to use is it still convenient?
Be sure you get a dual speed drill -- one speed for drilling and one for driving screws. Most (all?) cheap drills lack dual speed . In my opinion, the higher speeds, suitable for drilling, are too fast for convenient screw driving. You'll probably find one of the primary uses for your cordless drill is driving screws -- they're often called drill-drivers. I've never seen a single-speed cordless drill geared slow enough for screw driving, but if I could find a cheap one I'd probably give it a try -- the drilling may be slow, but it will work. Driving screws at high speeds is a problem.