The actual photography should account for about 15%+ of the total budget. And one thing to keep in mind regardless of cost - you'll want to get along with your photographer. This might sound like a silly thing to say -- but this person is going to be "in your face" the whole day and if the photographer you've chosen is even slightly annoying to you, you might want to consider looking else where.
There are so many different photography styles out there as well, so my recommendation is to first take a look at the the photographers website, see if you like their style of work, be honest with yourself. Then, put together a list of the photographers you like, after that look at their package prices - then meet with your top 3 and see where things go from there. Take a look at the pictures below and click any of them to bring you to that photographers website.
Some other great photographers to take a peek at are Power's and Amantez, I just didn't have time to post their images. There are so many great photographers to choose from! Just take your time, these are images you'll have for life!