It's been a while, but some thoughts...
-your college may have some kind of student assistance service that helps with finding roommates or accepts advertisements for students looking for them
-do interview potential roommates to get a feel for their vibe
-do mention your dog so those with allergies or dislikes won't waste both of your time
-do mention your art at least so those who would be bothered by art materials (I am sensitive to the presence of solvents etc) won't waste both of your time
-rent is generally split 50-50 as are utilities unless there is some huge imbalance in the amenities each enjoys- for instance if one occupies a large bedroom with ensuite bathroom while the other has a small bedroom and uses the public bathroom. Some address this imbalance by trading rooms every six months
-if you have both names on the lease each is liable for rent in case of default, but if only one name is on the lease s/he is solely responsible for all costs if the other defaults; OTOH if both are on the lease and it doesn't work out it's harder for one or the other to leave.

Finding a decent roommate can be a very tricky thing.. Definitely draw up some sort of contract.

Here is a link that might be useful: minneapolis apartments