I'll add yet another Frame Destination recommendation- I've never used them for frames (I have a good source of handmade ones), but I met Mark (owner) at PhotoPlus this year, was really impressed with what they were offering, and have bought cut mat boards and acrylic from them in the past couple of months. Everything has arrived on schedule (if not ahead of schedule), in great shape, and well made. Their prices are excellent, too (literally half of a local place on the acrylic).
Dan