My school kept all clinicals very local so I was never on the searching end.  However, students from other programs would email our ACCE when they were coming to our city for placements.  Our ACCE would then email blast all of the students in our program with that info.  Since my husband and I had a house with a few extra bedrooms, we rented rooms out to quite a few students that way.  It was a fun experience, and most said our 'rent' was a steal compared to their other options.  Obviously this is only going to work if there's a program where you are going, but any college/university may be able to give you some direction.  On the same token, I've heard some programs keep a sort of directory to help future students, based on where former students stayed.
Other options I've heard from friends, for better or worse...
-extended stay (pricey)
-staying with undergrad friends
-staying with a friend's parents (she said this was awesome and came with home-cooked meals)
-finding a room for rent online (potentially dangerous disaster in this case)
-renting a basement apartment from an elderly woman in a rural area