I thought I might 'bump' this thread as the Walker Cup approaches. Perhaps you are on the fence and thinking about coming, but don't have accommodations and are assuming not much is available anymore. Or maybe you've just put off making a hotel reservation.
A GCA.com member from my hometown is coming in on Friday and originally had booked a place in downtown Philly as most places out on the Main Line are booked, plus it appears easy to take the Septa R5 commuter rail train out from Center City to get to Merion. Well, the R5 Ardmore stop is still a nice little hike to the course (about 1 mile).
I've checked to see that my school's conference center (Villanova Conference Center) still has rooms available and the convenience of getting to the matches could not be easier as the R100 train has a station right next to the Conference Center (called the County Line stop), and you just take that down 8 stops to the Ardmore Avenue station and you are right next to the course!