There are many, many lighting threads already. If you do a search for "headlights" you'll probably find what you're looking for.
We bought a 2013 Sahara about 4 weeks ago. I thought the factory headlights were pretty lame and I searched around the forum to see what others have done. Although there are some nice (and expensive) aftermarket kits, some owners have had the dealer tell them it would void the warranty if an electrical issue popped up that could be blamed on the non-factory lighting causing a current imbalance.
I didn't want to deal with the potential hassle of all that so I went with a set of Philips H13 9008 X-treme Power Headlight Bulbs. They're a bit better than the stock bulbs but probably not as good as some $700 aftermarket kit which may void the warranty.