My FI and I booked our limo and shuttles for the big day. We're getting a limo bus from Limo Today and 2 motor coach shuttles from THG Transport. Both companies have been very courteous and helpful so far. There's a few administrative items that are moving slower than I'd like (one still needs to send me the final contract for the vehicle and one still hasn't booked my credit card), but I'm hopeful that those are just signs of being busy and not an indication of further problems to come.
Hope everyone is having similar luck in finishing up their vendor searches!